森 千里

Abstract Background The association between delivery mode and subsequent development of diseases is a growing area of research. Cesarean delivery affects the diversity of the microbiota in the infant gut, which may be associated with gastrointestinal disorders, including functional constipation, in infants. In this study, we investigated the association between delivery mode and prevalence of functional constipation in 3-year-old Japanese toddlers. Methods This study used data from the Japan Environment and Children’s Study, an ongoing nationwide birth cohort study. We analyzed 71,878 toddler–mother pairs. The presence of functional constipation was determined according to the Rome III diagnostic criteria. Odds ratios and 95% confidence intervals were calculated using logistic regression analysis. Results The prevalence of functional constipation in 3-year-old Japanese toddlers was estimated to be 12.3%. Logistic regression analysis revealed that the prevalence of functional constipation was higher in toddlers born by cesarean delivery (13.1%) compared with those born by vaginal delivery (12.1%), independent of 22 confounders (adjusted odds ratios = 1.064, 95% confidence interval = 1.004–1.128). Conclusions We determined the prevalence of functional constipation in 3-year-old Japanese toddlers and found that delivery mode was associated with the prevalence of functional constipation in Japanese toddlers.

Maternal tobacco smoke exposure during pregnancy impairs fetal body size, including head circumference (HC) at birth; however, the mechanism still remains unclear. This analysis using a large prospective cohort study evaluated the impact of maternal tobacco exposure on their offspring's HC and the relationship with placental weight ratio (PWR) and placental abnormalities. Parents-children pairs (n = 84,856) were included from the 104,065 records of the Japan Environmental and Children's Study. Maternal perinatal clinical and social information by self-administered questionnaires, offspring's body size, and placental information were collected. Data were analyzed with binominal logistic regression analysis and path analysis. Logistic regression showed significantly elevated adjusted odds ratio (aOR) (1.653, 95% CI 1.387-1.969) for the impact of maternal smoking during pregnancy on their offspring's smaller HC at birth. Maternal exposure to environmental tobacco smoke in the non-smoking group did not increase aOR for the smaller HC. Path analysis showed that maternal smoking during pregnancy decreased the offspring's HC directly, but not indirectly via PWR or placental abnormalities. The quitting smoking during pregnancy group did not increase aOR for the smaller HC than the non-smoking group, suggesting that quitting smoking may reduce their offspring's neurological impairment even after pregnancy.

Abstract Purpose N-3 polyunsaturated fatty acids (n-3 PUFAs), which are an important nutrient for humans, are particularly essential to the growth and development of the central nervous system (CNS) in fetuses and infants. Consequently, sufficient n-3 PUFA intake by mothers during pregnancy is considered to contribute to CNS development in their infants. CNS development is known to be associated with sleep, but no large epidemiological studies have yet confirmed that n-3 PUFA intake during pregnancy is associated with infants’ sleep. Methods After exclusion and multiple imputation from a dataset comprising 104 065 records from the Japan Environment and Children’s Study (JECS), we examined 87 337 mother–child pairs for the association between mothers’ fish and n-3 PUFA intakes and risk of their infants sleeping less than 11 h at 1 year of age. Results Multiple logistic regression analysis with the lowest quintile used as a reference revealed odds ratios for the second through fifth quintiles of 0.81 (95% confidence interval [95% CI] 0.76–0.87), 0.81 (95% CI 0.76–0.87), 0.78 (95% CI 0.72–0.84), and 0.82 (95% CI 0.76–0.88) for fish intake (p for trend < 0.001) and 0.90 (95% CI 0.84–0.97), 0.88 (95% CI 0.81–0.94), 0.88 (95% CI 0.82–0.95), and 0.93 (95% CI 0.86–0.998) for n-3 PUFA intake (p for trend = 0.04). Conclusions Low fish intake during pregnancy may increase the risk of infants sleeping less than 11 h at 1 year of age. This relationship may have been mediated by maternal n-3 PUFA intake and infant neurodevelopment, but further evidence from interventional and other studies is needed to determine the appropriate level of fish intake during pregnancy. Trial registration The Japan Environment and Children’s Study, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000035091 (Registration no. UMIN000030786).

Background: Hypertensive disorders of pregnancy (HDP) are one of the most common medical conditions that women encounter during pregnancy. Whether or not hypertensive disorders of pregnancy (HDP) are associated with allergic conditions in the offspring is unclear. This study used data from a large Japanese birth cohort to investigate whether HDP contributes to the development of allergic conditions in the offspring at 3 years. We also assessed the effect of blood pressure at different pregnancy trimesters on children's allergies. Methods: We obtained data from the Japan Environment and Children's Study (JECS), which included 104 062 fetal records. After data selection, we analyzed 77 505 mother–child pairs, using logistic regression models to examine the relationships between HDP or the mother's blood pressure and their children's allergic conditions. In addition, we also evaluated the effect of HDP during pregnancy on allergies with a propensity score matched dataset, using a logistic regression model that predicts the conditional probability of whether a mother belonged to the HDP or non-HDP group. Results: Among the 77 505 mothers eligible for analysis, 2334 (3.0%) had HDP. Percentages of women with hypertension were 1.7% in early gestation, 1.0% in mid-gestation, and 1.6% in late gestation. After adjusting for multiple potential confounders, HDP contributed nothing to allergy development in offspring. Children born to women with hypertension were no more likely than those without to have allergic conditions at 3 years of age. The propensity score matched dataset showed similar findings. Conclusion: HDP and high blood pressure during pregnancy are apparently not risk factors for developing allergy in offspring. This information may help clinicians in counseling women who suffered HDP during pregnancy.

CONTEXT: Maternal cholesterol is important for fetal development. Whether maternal serum total cholesterol (maternal TC) levels in mid-pregnancy are associated with small- (SGA) or large- (LGA) for-gestational-age independent of pre-pregnancy body mass index (BMI) and weight gain during pregnancy is inconclusive. OBJECTIVE: To prospectively investigate the association between maternal TC in mid-pregnancy and SGA or LGA. DESIGN AND SETTING: The Japan Environment and Children's Study is a nationwide prospective birth cohort study in Japan. PARTICIPANTS: A total of 37,449 non-diabetic, non-hypertensive mothers with singleton birth at term without congenital abnormalities. OUTCOME MEASURES: Birth weight for the gestational age <10 percentile and ≥90 percentile were respectively defined as SGA and LGA by the Japanese neonatal anthropometric charts. RESULTS: The mean gestational age at blood sampling was 22.7±4.0 weeks. After adjustment for maternal age, sex of child, parity, weight gain during pregnancy, pre-pregnancy BMI, smoking, alcohol drinking, blood glucose levels, household income, and Study Areas, one standard deviation decrement of maternal TC was linearly associated with SGA [odds ratio (OR): 95% confidence intervals (CI) = 1.20: 1.15-1.25]. In contrast, one standard deviation increment of maternal TC was linearly associated with LGA [OR: 95% CI = 1.13: 1.09-1.16]. Associations did not differ according to pre-pregnancy BMI and gestational weight gain (p for interaction>0.20). CONCLUSION: Maternal TC levels in mid-pregnancy were associated with SGA or LGA in Japanese. Maternal TC in mid-pregnancy may help to predict SGA and LGA. Favorable maternal lipid profiles for fetal development must be explored.

Chemokine (C-C motif) ligand 17 (CCL17) is a pro-allergic factor: high CCL17 levels in cord blood (CB) precede later allergic predisposition. Short-chain fatty acid (SCFA) treatment during pregnancy has been shown to protect mouse pups against allergic diseases. The maternal microbial metabolome during pregnancy may affect fetal allergic immune responses. We therefore examined the associations between CB CCL17 and gut SCFA levels in healthy pregnant Japanese women. CB CCL17 serum levels at birth, and maternal non-specific IgE levels in maternal sera at 32 weeks of gestation were measured. Maternal stool samples were collected at 12 (n = 59) and 32 (n = 58) weeks of gestation for gut microbiota analysis, based on barcoded 16S rRNA sequencing and metabolite levels. The CB CCL17 levels correlated negatively with butyrate concentrations and positively with isobutyrate at 12 weeks; CB CCL17 correlated positively with valerate and lactate at 32 weeks. Similarly, butyrate levels correlated negatively with maternal non-specific IgE levels, whereas the lactate concentration correlated positively with IgE levels. At 32 weeks, the Shannon diversity index (SDI) of Firmicutes and Proteobacteria correlated negatively with CB CCL17 levels, while those of the total microbiota correlated positively with the CB CCL17 levels. These metabolites may alter fetal immune responses. This study provides the first link between maternal metabolites during pregnancy and the risk of allergic diseases in human offspring.

医師、歯科医師、パラメディカル(コ・メディカル)を含むすべての医療従事者にとって、人体の構造を学ぶ解剖学は重要な学問である。パラメディカルの学生にとって、解剖見学実習は人体構造を学ぶ上で有益であるが、一般的にはその機会は制限されている。ここで、物事に関する興味・関心は教育における重要な変数であり、例えば興味・関心と成績の間には正の相関があることが報告されている。本研究では、解剖見学実習に参加した看護師、鍼灸師、薬剤師、理学療法士・作業療法士、栄養士、救急救命士の各養成校の学生に対してアンケート調査を実施し、人体の解剖学的構造において特に興味・関心を有する部位の調査を行った。2013年7月から2016年3月の間に、千葉大学医学部において解剖見学実習に参加したパラメディカル学生878人を調査対象とした。解析結果は、1)特に学生にとって興味のある器官系は神経系(6領域全て)、循環器系(看護師、鍼灸師、薬剤師、栄養士、救急救命士)、消化器系(看護師、薬剤師、栄養士、救急救命士)、骨筋系(鍼灸師および理学療法士・作業療法士)であったこと、2)これらの器官系について、特に興味のある器官系構成要素は各専門領域間で異なっていたこと、3)神経系と循環器系は、看護領域の専門学校学生1年生と2年生の両方にとって、特に興味のある器官系であったこと、4)両器官系において特に興味のある器官系構成要素は1年生と2年生の間で異なり、しかしながら「脳」は神経系において両学年にとって特に興味のある器官系要素であったことを示した。これらの各パラメディカル領域における学生の興味・関心の違いは、今後、各領域の専門性に特化した解剖学の教育方法を構築していくにあたり、重要な知見となるものと思われる。(著者抄録)

<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p>Postpartum depression is one of the most commonly experienced psychological disorders for women after childbirth, usually occurring within one year. This study aimed to clarify whether women with delivery with anesthesia, including epidural analgesia, spinal-epidural analgesia, and paracervical block, had a decreased risk of postpartum depression after giving birth in Japan.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>The Japan Environment and Children’s Study (JECS) was a prospective cohort study that enrolled registered fetal records (n = 104,065) in 15 regions nationwide in Japan. Binomial logistic regression analyses were performed to calculate the adjusted odd ratios (aORs) for the association between mode of delivery with or without anesthesia and postpartum depression at one-, six- and twelve-months after childbirth.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>At six months after childbirth, vaginal delivery with anesthesia was associated with a higher risk of postpartum depression (aOR: 1.233, 95% confidence interval: 1.079–1.409), compared with vaginal delivery without analgesia. Nevertheless, the risk dropped off one year after delivery. Among the pregnant women who requested delivery with anesthesia, 5.1% had a positive Kessler-6 scale (K6) score for depression before the first trimester (<jats:italic>p</jats:italic> &lt; 0.001), which was significantly higher than the proportions in the vaginal delivery without analgesia (3.5%).</jats:p> </jats:sec><jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Our data suggested that the risk of postpartum depression at six months after childbirth tended to be increased after vaginal delivery with anesthesia, compared with vaginal delivery without analgesia. Requests for delivery with anesthesia continue to be relatively uncommon in Japan, and women who make such requests might be more likely to experience postpartum depressive symptoms because of underlying maternal environmental statuses.</jats:p> </jats:sec>

To conduct a long-term birth cohort study that includes genetic analysis, it is crucial to understand the attitudes of participants to genetic analysis and then take appropriate approaches for addressing their ambiguous and negative attitudes. This study aimed to explore participants' attitudes toward genetic analysis and associated background factors among mothers who were enrolled in a large Japanese birth cohort. A questionnaire was sent to participants' households, and the responses of 1762 mothers (34.0%) were used for the study. The majority of mothers recognized genetic analysis for themselves and their children and sharing of genetic data as beneficial. A low knowledge level of genomic terminology was associated with ambiguous attitudes toward genetic analysis and data sharing. Education level was positively associated with the recognition of the benefits of genetic analysis. Concern about handling genetic information was associated with the unacceptability of data sharing. Trust was associated with the approval of genetic analysis. Most mothers preferred that genetic analysis results be returned. These findings suggest the need for multiple efforts to maximize participants' acceptance of genetic analysis, such as utilizing an educational approach to encourage familiarity with genetics/genomics, optimizing explanations for different educational levels, and explicitly disclosing the handling policy for genetic information.

Abstract Kawasaki disease (KD) is an acute systemic vasculitis that mainly affects infants and young children. The etiology of KD has been discussed for several decades; however, no reproducible risk factors have yet been proven. We used the Japan Environment and Children’s Study data to explore the association between the causal effects of exposure during the fetal and neonatal periods and KD onset. The Japan Environment and Children’s Study, a nationwide birth cohort study, has followed approximately 100,000 children since 2011. We obtained data on exposures and outcomes from the first trimester to 12 months after birth. Finally, we included 90,486 children who were followed for 12 months. Among them, 343 children developed KD. Multivariate logistic regression revealed that insufficient intake of folic acid during pregnancy (odds ratio [OR], 1.37; 95% CI 1.08–1.74), maternal thyroid disease during pregnancy (OR, 2.03; 95% CI 1.04–3.94), and presence of siblings (OR, 1.33; 95% CI 1.06–1.67) were associated with KD onset in infancy. In this study, we identified three exposures as risk factors for KD. Further well-designed studies are needed to confirm a causal relationship between these exposures and KD onset.

Abstract This research aimed to examine the efficacy of the early initiation of breastfeeding within 1 h of birth, early skin-to-skin contact, and rooming-in for the continuation of exclusive breastfeeding until 6 months postpartum. The research used data from the Japan Environment and Children’s Study (JECS), a nationwide government-funded birth cohort study. A total of 80,491 mothers in Japan between January 2011 and March 2014 who succeeded or failed to exclusively breastfeed to 6 months were surveyed in JECS. Multiple logistic regression model was used to analyse the data. The percentage of mothers who succeeded in exclusively breastfeeding to 6 months is 37.4%. Adjusted odds ratios were analysed for all 35 variables. Early initiation of breastfeeding (adjusted odds ratio [AOR]: 1.455 [1.401–1.512]), early skin-to-skin contact (AOR: 1.233 [1.165–1.304]), and rooming-in (AOR: 1.567 [1.454–1.690]) affected continuation of exclusive breastfeeding. Regional social capital (AOR: 1.133 [1.061–1.210]) was also discovered to support the continuation of breastfeeding. In contrast, the most influential inhibiting factors were starting childcare (AOR: 0.126 [0.113–0.141]), smoking during pregnancy (AOR: 0.557 [0.496–0.627]), and obese body type during early pregnancy (AOR: 0.667 [0.627–0.710]).

BACKGROUND: The ulnar collateral ligament complex, particularly the anterior oblique ligament (AOL), is mainly a static stabilizer controlling valgus. Various studies have been conducted on the kinematics of elbow joints after ligament cutting; however, no biomechanical studies have measured the tension applied to the ligament. Finite element modeling (FEM) is a very useful tool for biomechanical evaluation of the elbow. However, an accurate FEM of elbow joints cannot be developed without information on the potential tension of ligaments applied during the flexion and extension of elbow joints. We believe that FEM of the elbow joint could be obtained by measuring the material properties and potential tension of the ligament applied during the flexion and extension of the elbow joint. This study aimed to measure the potential tension and material properties of the ligament during the flexion and extension of the elbow, by identifying the relation between ligament length and tension using mechanical testing. METHODS: We included 10 elbows harvested from 7 fresh-frozen cadavers. The average age of the cadavers was 83.7 ± 5.65 years, and the samples included 8 elbows from 6 male cadavers and 2 elbows from 1 female cadaver. We measured the ligament length at each elbow angle by changing the elbow joint from 0° to 120° in 15° intervals. Thereafter, we extracted the AOL and divided into an anterior band (AB) and a posterior band (PB) and performed a mechanical test to calculate ligament stress. RESULTS: The ligament length of the AB gradually decreased as the flexion angle increased. Conversely, the ligament length of the PB gradually increased as the flexion angle increased. AB and PB lengths were approximately the same between 60° and 75°. The average ligament tension and stress of the AB gradually increased with elbow extension. In contrast, the average ligament tension and stress of the PB gradually increased with elbow flexion. The tension and stress of the AB and PB were balanced around the elbow joint at 60°. CONCLUSION: The AB was tenser on elbow extension, and the PB was tenser following elbow flexion. Also, the angle at which the AOL stress was equalized was 60°, suggesting that ∼60° is the angle at which the AOL is unlikely to be damaged.

Apgar score (AS) is a well-established tool for assessing viability of newborns, and its association with subsequent child development has been suggested. We aimed to assess whether Apgar scores (ASs) ≥ 7 (generally considered normal) are associated with the developmental status at 3 years of age while adjusting for perinatal and socioeconomic confounders. We extracted the data of ASs at 1 and 5 min among participants of the Japan Environment and Children’s Study datasets, which were used in this nationwide cohort study. The outcomes comprised developmental status that was less than each cutoff value for the following five domains of the Ages &amp Stages Questionnaire (Japanese version, 3rd edition): communication, gross and fine motor, problem-solving, and personal-social domains. For this objective, we conducted multivariable logistic regression analyses on the data of 54,716 children. Compared with ASs ≥ 9 at 5 min, the adjusted odds ratios (aOR) for delayed development in children with ASs ≤ 8 were 1.31 (95% confidence interval, 1.11–1.56), 1.20 (1.04–1.38), and 1.16 (1.01–1.34), respectively, for gross and fine motor, and problem-solving domains. Among neonates with ASs ≤ 8 at 1 min, when those with ASs ≤ 8 at 5 min were compared with those with ASs ≥ 9 at 5 min, the aOR for gross motor domain was 1.34 (1.11–1.61). Conclusion: ASs ≤ 8 compared with those ≥ 9 at 5 min, even considering the change of AS from 1 to 5 min, were associated with increased ORs for developmental delay in 3-year-olds. Even ASs that are considered normal might affect the subsequent development.What is Known:• Apgar score is a general tool for evaluating the vitality of newborns. It is also basically measured at 1 minute and 5 minutes after birth and the scores of ≥7 are considered normal.• The Apgar scores at each minute affect clinical findings of neonates after birth and the subsequent long-term development.What is New:• Neonates with Apgar scores of ≤8 at 5 minutes compared with those of ≥9, including the change in Apgar score from 1 minute to 5 minutes, are associated with increased odds ratios for developmental status at 3 years of age adjusting for perinatal and socioeconomic confounders.

[This corrects the article DOI: 10.1016/j.waojou.2019.100065.].

It is well known that the indoor environment, particularly indoor air quality (IAQ), has significant effects on building-related symptoms (BRSs) in humans, such as irritation of mucosal membranes, headaches, and allergies, such as asthma and atopic dermatitis. In 2017, Chiba University launched the "Chemiless Town Project Phase 3" to investigate the relationship between IAQ and human health. Two laboratory houses (LHs) were built on a university campus in which the interiors and exteriors were similar, but the levels of indoor air volatile organic compounds (VOCs) were different. A total of 141 participants evaluated IAQ using their sensory perception. There was a significant relationship between differences in VOC levels and BRSs occurrence (OR: 6.89, 95% CI: 1.40-33.98). It was suggested that people with a medical history of allergies (OR: 5.73, 95% CI: 1.12-29.32) and those with a high sensitivity to chemicals (OR: 8.82, 95% CI: 1.16-67.16) tended to experience BRSs. Thus, when buildings are constructed, people with a history of allergies or with a sensitivity to chemicals may be at high risk to BRSs, and it is important to pay attention to IAQ to prevent BRSs.

Inappropriate gestational weight gain (GWG), either above or below the recommended values, has been associated with an increased risk of adverse obstetric outcomes. To evaluate the risks of GWG for foetal acidosis according to pre-pregnancy body mass index (BMI) and mode of delivery, we analysed women with singleton pregnancies between 2011 and 2014 in the Japan Environment and Children’s Study. Participants (n = 71,799) were categorised according to pre-pregnancy BMI. GWG was categorised into insufficient, appropriate, or excessive. Foetal acidosis was defined as umbilical artery pH (UmA-pH) &lt 7.20 or &lt 7.10. Multiple logistic regressions were performed for each BMI category to identify the risks of GWG for foetal acidosis, accounting for the mode of delivery. Excessive GWG was significantly associated with increased foetal acidosis in overweight women and in women whose pre-pregnancy BMI was 23.0–25.0 kg/m2 especially in those with vaginal deliveries. Conversely, excessive GWG was not significantly associated with increased foetal acidosis in obese women and in women whose pre-pregnancy BMI was ≥ 25.0 kg/m2.

The Edinburgh Postnatal Depression Scale (EPDS) is frequently used to screen for postpartum depression. However, its factor structure exhibits noticeable inconsistencies between studies. We examined the EPDS at two postpartum time points using a large dataset from outside Western countries. Participants were 91,063 mothers in an ongoing birth cohort of the Japan Environment and Children’s Study. One-, two-, and three-factor structures of the EPDS at 1- and 6-months postpartum were extracted using exploratory factor analysis (EFA) with oblique rotation. Goodness-of-fit indices of extracted factor structures were compared with prior ones by conducting a confirmatory factor analysis (CFA). CFA revealed that a three-factor model extracted from the current EFA—anxiety (items 3, 4, 5, and 6), depression (items 7, 9, and 10), and anhedonia (items 1 and 2)—showed acceptably high goodness-of-fit and invariability across time. These three factors explained about 65% of the total variance with good reliability (all Cronbach’s αs ≥ 0.70). Most three-factor structures (vs. two-) showed higher goodness-of-fit indices. In conclusion, although we only examined the postpartum period, the EPDS likely comprises three dimensions: anxiety, depression, and anhedonia. Our findings raise questions about the one- or two-factor structure of the EPDS. Trial registration: UMIN000030786.

Background: Although emerging evidence indicates a relation between maternal intake of fish and improved child neurodevelopment, the results are inconsistent. Objectives: This study investigated whether dietary consumption of fish during pregnancy is associated with offspring neurodevelopment at age 6 mo and 1 y. As exploratory research, we also examined the association between consumption of PUFAs and neurodevelopment at the same time points. Methods: After exclusion and multiple imputation from a dataset comprising 104,065 records from the Japan Environment and Children's Study, we evaluated 81,697 and 77,751 mother-child pairs at age 6 mo and 1 y, respectively. Results: Maternal fish intake during pregnancy was independently associated with reduced risk of delay in problem-solving at age 6 mo (lowest compared with highest quintile OR = 0.88 95% CI: 0.79, 0.99 P-trend = 0.01) and in fine motor skills (highest quintile OR = 0.90 95% CI: 0.81, 0.99 P-trend = 0.02) and problem-solving (fourth quintile OR = 0.89 95% CI: 0.81, 0.98 and highest quintile OR = 0.90 95% CI: 0.81, 0.99 P-trend = 0.005) at age 1 y. Dietary intake of total n-3 PUFAs was associated with reduced risk of delay in fine motor skills at 6 mo, and in fine motor skills and problem-solving at 1 y. Dietary intake of total n-6 PUFAs was associated with reduced risk of delay in communication and fine motor skills at 6 mo, and in gross motor skills, fine motor skills, and problem-solving at 1 y. In contrast, the dietary n-6/n-3 ratio was positively associated with increased risk of delay in problem-solving at 1 y. Conclusions: The results of this study suggest there might be beneficial effects of fish intake during pregnancy on some domains of child psychomotor development and this effect might be partially explained by PUFA intake from fish. Trial registration: UMIN000030786.

Introduction: Past studies have shown that maternal anemia is associated with a heavy placenta or a higher placental weight/birthweight (PW/BW) ratio. Although these findings suggest a non-linear relationship between maternal hemoglobin concentration and PW/BW ratio, this relationship has not been closely examined. Methods: We evaluated 83,354 singletons and their mothers in a nation-wide birth cohort study, the Japan Environment and Children's Study (JECS). The associations between maternal hemoglobin concentration and placental weight, birthweight, and PW/BW ratio were assessed. Results: Mean placental weight was significantly higher in women with moderate or severe anemia (576 [183] g), but not in women with elevated hemoglobin levels (564 [117] g), compared with in women with normal hemoglobin levels (560 [115] g). In contrast, mean PW/BW ratio was significantly higher in women with moderate or severe anemia (0.190 [0.049]) or elevated hemoglobin levels (0.189 [0.033]) than in women with normal hemoglobin levels (0.185 [0.033]). In a regression analysis with cubic spline, a U-shaped relationship was found between maternal hemoglobin concentration and PW/BW ratio. Discussion: We demonstrated non-linear and concentration-dependent relationships between maternal hemoglobin concentration and placental weight, birthweight, and PW/BW ratio. Although the mechanisms underlying these associations are not fully understood, we suggest that low or elevated hemoglobin concentration may lead to placental compensatory hypertrophy and fetal growth restriction. Prevention and proper management of anemia before and during pregnancy are important for a well-functioning placenta and favorable fetal growth.

This study aimed to describe the distribution of pregnancies with medical and obstetric complications based on the Japan Environment and Children's Study (JECS). We evaluated the distribution of the history of obstetric/gynaecological diseases, the history of obstetric labour complications, pregnancy with medical and surgical complications, and obstetric labour complications in participants in the JECS. Of 100,818 pregnant women with medical record entries after delivery, 15,305 (15.2%) had medical and surgical complications in pregnancy and 46,756 (46.4%) experienced obstetric labour complications. The proportion of pregnancies with heart disease, kidney disease and hepatitis was 0.3%, 0.3% and 0.1%, respectively. Gestational diabetes was diagnosed in 2715 (2.7%) women. The proportion of women with mild and severe gestational hypertension was 2.3% and 1%, respectively. The JECS is the largest birth cohort in Japan. These data will provide useful, basic information for perinatal care in Japan.IMPACT STATEMENT What is already known on this subject? Epidemiological studies have suggested that pre-existing diseases and complications of pregnancy, such as heart disease in pregnancy, gestational hypertension and gestational diabetes, may have implications for pregnancy outcomes, as well as for children's health and development. What the results of this study add? We evaluated the distribution of the history of obstetric/gynaecological diseases, the history of obstetric labour complications, medical and surgical complications in pregnancy, and obstetric labour complications using data from the Japan Environment and Children's Study (JECS).

Background: Previous studies revealed positive, negative, and no influence of social capital on the health outcomes of pregnant women. It was considered that such differences were caused by the disparities of outcome measures and sample sizes between studies. Our chief aim was to verify the positive influence of social capital on the health condition of pregnant women using established health outcome measures and large-scale nationwide survey data. Methods: We employed questionnaire survey data from 79,210 respondents to the Japan Environment and Children's Study, and physical and mental component summary scores from the 8-Item Short-Form Health Survey as outcome measures. We estimated the effect of individual and neighborhood social capitals on physical and mental component summary scores. To consider the property that the richness of social capital would be generally determined by individual characteristics, and to estimate the causal influence of social capital on health without bias caused by said property, we adopted average treatment effect estimation with inverse probability weighting. Generally, average treatment effects are based on the difference of average outcomes between treated and untreated groups in an intervention. In this research, we reckoned individuals' different levels of social capital as a kind of non-randomized treatment for respective individuals, and we applied average treatment effect estimation. The analysis regarded pregnant women with the lowest level of social capital as untreated samples and women with other levels of social capitals as treated samples. Results: For mental component summary score, the maximum average treatment effects in the comparison between the lowest and highest levels of social capital were approximately 4.4 and 1.6 for individual and neighborhood social capital, respectively. The average treatment effects for the physical component summary score were negligible for both social capital types. Conclusions: Social capital particularly contributes to improving mental component summary score in pregnant women. The likelihood of a mentally healthy pregnancy may be increased by enhancing social capital.

The purpose of the present study was to investigate associations of dietary intake including vitamin D, folate, and n-3 and n-6 polyunsaturated fatty acids (PUFA) in pregnant women with broad autism phenotype (BAP). The Japan Environment and Children’s Study is a government-funded birth cohort study. All complete data of 92,011 were analyzed. The Japanese version of the Autism Spectrum Quotient was used to assess mothers’ BAP level, and a food frequency questionnaire was used to estimate their dietary intake. Mothers with BAP consumed less vegetables, fruits, and fish and shellfish, and they consumed lower folate, vitamin C, vitamin D, and n-3 PUFA than their counterparts. Dietary intervention should be considered for pregnant women with high BAP scores.

Background: The neurotoxicity of general anesthesia to the developing human brains is controversial. We assessed the associations between surgery under general anesthesia in infancy and development at age 1 year using the Japan Environment and Children's Study (JECS), a large-scale birth cohort study. Methods: In the JECS, 103,062 pregnancies and 104,065 fetuses were enrolled between January 2011 and March 2014. Of the 100,144 registered live births, we excluded preterm or post-term infants, multiple births, and infants with chromosomal anomalies and/or anomalies of the head or brain. Data on surgical procedures under general anesthesia in infancy were collected from self-administered questionnaires by parents at the 1-year follow-up. Developmental delay at age 1 year was assessed using the Japanese translation of the Ages and Stages Questionnaires, Third Edition (J-ASQ-3), comprising five developmental domains. Results: Among the 64,141 infants included, 746 infants had surgery under general anesthesia once, 90 twice, and 71 three or more times. The percentage of developmental delay in the five domains of the J-ASQ-3 significantly increased with the number of surgical procedures. After adjusting for potential confounding factors, the risk of developmental delays in all five domains was significantly increased in infants who had surgery under general anesthesia three times or more (adjusted odds ratios: for communication domain 3.32 gross motor domain 4.69 fine motor domain 2.99 problem solving domain 2.47 personal-social domain 2.55). Conclusions: Surgery under general anesthesia in infancy was associated with an increased likelihood of developmental delay in all five domains of the J-ASQ-3, especially the gross motor domain at age 1 year. The neurodevelopment with the growth should be further evaluated among the children who had surgery under general anesthesia. Trial registration: UMIN Clinical Trials Registry (number: UMIN000030786).

Background: Adjuvants used in inactivated vaccines often upregulate type 2 immunity, which is dominant in allergic diseases. We hypothesised that cumulative adjuvant exposure in infancy may influence the development of allergies later in life by changing the balance of type 1/type 2 immunity. We examined the relationship between immunisation with different vaccine types and later allergic disease development. Methods: We obtained information regarding vaccinations and allergic diseases through questionnaires that were used in The Japan Environment and Children's Study (JECS), which is a nationwide, multicentre, prospective birth cohort study that included 103,099 pregnant women and their children. We examined potential associations between the initial vaccination before 6 months of age and symptoms related to allergies at 12 months of age. Results: Our statistical analyses included 56,277 children. Physician-diagnosed asthma was associated with receiving three (aOR 1.395, 95% CI 1.028-1.893) or four to five different inactivated vaccines (aOR 1.544, 95% CI 1.149-2.075), compared with children who received only one inactivated vaccine. Similar results were found for two questionnaire-based symptoms, i.e. wheeze (aOR 1.238, 95% CI 1.094-1.401 three vaccines vs. a single vaccine) and eczema (aOR 1.144, 95% CI 1.007-1.299 four or five vaccines vs. a single vaccine). Conclusions: Our results, which should be cautiously interpreted, suggest that the prevalence of asthma, wheeze and eczema among children at 12 months of age might be related to the amount of inactivated vaccine exposure before 6 months of age. Future work should assess if this association is due to cumulative adjuvant exposure. Despite this possible association, we strongly support the global vaccination strategy and recommend that immunisations continue. Trial registration: UMIN000030786.

BACKGROUND: There are growing concerns about the increasing rate of caesarean section (CS) worldwide. Various strategies have been implemented to reduce the proportion of CS to a reasonable level. Most research on medical indications for CS focuses on nationwide evaluations. Comparative research between different countries is sparse. The aim of this study is to evaluate differences in rate and indications for CS between Japan and Germany in 2012 and 2013. METHODS: Comparison of overall rate and medical indications for CS in two cohort studies from Germany and Japan. We used data from the German Perinatal Survey and the Japan Environment and Children's Study (JECS). RESULTS: We analyzed data of 1,335,150 participants from the German perinatal survey and of 62,533 participants from JECS and found significant differences between the two countries in CS rate (30.6% vs. 20.6%) and main medical indications: cephalopelvic disproportion (3.2% vs. 1.3%; OR: 2.4 (95%-CI: 2.2 - 2.6)), fetal distress (7.3% vs. 2.3%; OR: 3.4 (95%-CI: 3.2 - 3.6)) and past uterine surgery/repeat CS (8.4% vs. 8.8%; OR: 0.9 (95%-CI: 0.9 - 1)). CONCLUSION: There are differences in rate and medical indication for CS between Germany and Japan on population level. Fetal distress was identified as a medical indication for CS more often Germany than in Japan. Considering the substantial diagnostic uncertainty of electronic fetal monitoring (EFM) as the major indicator for fetal distress, it seems to be reasonable to rethink decision algorithms.

"Total" folate in blood has usually been measured to evaluate the folate status of pregnant women. However, folate is composed of many metabolites. The main substrate is 5-methyltetrahydrofolate (5-MTHF), with folic acid (FA) representing a very small component as an unmetabolized species in blood. We longitudinally evaluated 5-MTHF, FA and total homocysteine in maternal and cord blood from Japanese pregnant women. Subjects were 146 pregnant women who participated in the Chiba study of Mother and Child Health (C-MACH) prospective cohort study. Sera were obtained in early and late pregnancy, at delivery, and from cord blood. Species levels were measured by isotope-dilution mass spectrometry. Both 5-MTHF and FA levels were lower than reported levels from pregnant women in populations from countries with mandatory FA fortification. As gestational age progressed, serum 5-MTHF levels decreased, whereas serum FA levels were slightly reduced only at delivery compared to early pregnancy. A significant negative association between serum 5-MTHF and total homocysteine was shown at all examined times, but no associations with FA were evident. At delivery, cord 5-MTHF was significantly higher than maternal levels, while FA again showed no significant correlation. These results suggest that 5-MTHF is actively transported to the fetus through placental transporters and may reflect folate status during pregnancy as a physiologically important species.

Prenatal exposure to mercury in utero causes abnormal foetal growth and adverse outcomes. DNA methylation is currently considered a possible mechanism through which this occurs. However, few studies have investigated the association between prenatal exposure to mercury and DNA methylation in detail. This study aimed to clarify the relationship between prenatal exposure to total mercury (Hg) and DNA methylation and its associations with sex-specific characteristics in male and female offspring. In a birth cohort study known as the Chiba study of Mother and Child Health, the DNA methylation status in cord tissue and Hg concentrations in cord serum were examined. A total of 67 participants (27 males and 40 females) were analysed based on Spearman's correlations, adjusted by a false discovery rate of the sex of each offspring. Only one methylated locus was positively correlated with Hg concentrations in cord serum in male offspring, but not in female offspring, and was annotated to the haloacid dehalogenase-like hydrolase domain-containing protein 1 (HDHD1) gene on chromosome X. This locus was located in the intron of the HDHD1 gene body and is a binding site for the zinc finger protein CCCTC-binding factor. One of the other loci, located in HDHD1, was highly methylated in the group with higher mercury concentrations, and this locus was in the gene body of HDHD1. Our results suggest that prenatal exposure to Hg might affect the epigenetic status of male foetuses.

Evidence is mixed on the associations between physical activity during pregnancy and perinatal depression, and it is limited for different physical activity intensities. Data for 92,743 pregnant women from the Japan Environment and Children's Study were analyzed in this study. Psychological distress during pregnancy was assessed as moderate or severe using the Kessler Psychological Distress Scale (K6 5-12 and >= 13, respectively). Postpartum depression was assessed using the Edinburgh Postpartum Depression Scale (EPDS; cut-off score 9). Women with only light physical activity had significantly lower odds of psychological distress during pregnancy than those with no physical activity (K6 5-12: adjusted odds ratio [AOR] 0.86, 95% confidence interval [95%CI] 0.82, 0.90; K6 >= 13: AOR 0.64, 95%CI 0.58, 0.72). Women with a combination of light, moderate and vigorous physical activity had significantly higher odds of psychological distress during pregnancy (K6 5-12: AOR 1.32, 95%CI 1.18, 1.48; K6 >= 13: AOR 1.45, 95%CI 1.16, 1.81) and depression after childbirth (EPDS >= 9: AOR 1.42, 95%CI 1.24, 1.61). Physical activity intensity should be considered when assessing psychological distress risk during pregnancy and depression risk after delivery. Future research should evaluate specific physical activity programs with optimal intensity for pregnant women to prevent and treat their psychological distress and depression.

Herein, the concentrations of formic acid, acetic acid, and ammonia in samples of indoor air for 47 new houses were measured two weeks after completion. The houses were fabricated with light-gauge steel structures. The measurements were performed in living rooms and bedrooms without furniture and outdoors. Air samples were analyzed using ion chromatography. The mean values were 28 (living room), 30 (bedroom), and 20 μg m-3 (outdoor air) for formic acid; 166 (living room), 151 (bedroom), and 51 μg m-3 (outdoor air) for acetic acid; and 73 (living room), 76 (bedroom), and 21 μg m-3 (outdoor air) for ammonia. The total values of the three substances accounted for 39.4-40.7% of the sum of chemical compound values. The analyzed compounds were indicated by two principal components (PC), PC1 (30.1%) and PC2 (9%), with 39.1% total variance. Formic acid, acetic acid, and ammonia were positively aligned with PC1 and negatively aligned with PC2. Factors such as room temperature, aldehydes, and phthalates were positively aligned with PC1 and negatively aligned with PC2. Furthermore, concentrations of formic acid, acetic acid, and ammonia were significantly and positively correlated with room temperature (p < 0.05).

Background Nutritional requirements increase during pregnancy. However, relatively few studies have examined longitudinal changes in dietary intake from periconception to pregnancy. Here, we investigated changes in the intake of food and nutrients, and compliance with dietary reference intakes (DRIs) in pregnant women. Methods The Japan Environment and Children's Study, a nationwide multicenter prospective cohort study, included 30,373 pregnant women who answered a validated food frequency questionnaire repeatedly to assess changes in dietary intake in periconception and pregnancy. Energy-adjusted intakes of food groups and nutrients were described using the density method. The percentage of women not meeting DRIs was calculated. Results Of all foods groups examined, intake of food significantly increased from periconception to pregnancy for dairy products (mean difference 23.5 g/1000 kcal, 95% confidence interval [CI] 22.0-25.0 g/1000 kcal), confectionaries (2.0 g/1000 kcal, 1.8-2.2 g/1000 kcal), and soft drinks (1.3 g/1000 kcal, 0.3-2.3 g/1000 kcal). Of all nutrients examined, intake was significantly increased for calcium (mean difference 27 mg/1000 kcal, 95% CI 25-29 mg/1000 kcal), vitamin A (15 mu gRE/1000 kcal, 13-18 g/1000 kcal), and saturated fat (0.4% energy, 0.4-0.4% energy). The percentage of women not meeting DRIs increased for vitamin B group, vitamin C, saturated fat and salt. Conclusion We found that energy-adjusted intakes of calcium, vitamin A, and saturated fat increased from periconception to pregnancy, while intake of other nutrients did not increase. The percentage of women not meeting DRIs increased for water-soluble vitamins, saturated fat, and salt.

Aim To evaluate the association between use of assisted reproductive technology (ART) and mother-to-infant bonding. Methods Using nationwide birth cohort study with periodical follow-ups for mothers and children during pregnancy and at 1 year after delivery, mothers were classified following three groups; infertility group with ART: 2792 mothers; infertility group with non-ART treatment (ovulation induction and intrauterine insemination): 3835 mothers and unaided pregnancy group: 78 726 mothers. Data on maternal and child health as well as basic characteristics were collected via medical records and self-administered questionnaires. The Japanese version of Mother-to-Infant Bonding Scale was used to evaluate maternal bonding style. To evaluate the association between ART and maternal bonding toward babies, multivariate analysis was used with adjustment for potential confounders such as babies' sex, socio-economic status and history of maternal mental disorders. Results Multivariate logistic regression analysis indicated that ART was slightly but significantly associated with an increased risk of maternal lack of affection toward their newborn (adjusted odds ratio 1.10, 95% confidence interval 1.02-1.20), while non-ART was significantly associated with both maternal lack of affection and anger/rejection toward the newborn. No substantial association was observed between ART and overall Mother-to-Infant Bonding Scale score (adjusted odds ratio 1.03, 95% confidence interval 0.94-1.12). Very slight negative correlations were observed between poor mother-to-infant bonding and good infant mental and physical development at both 6 months and 1 year. Conclusion ART may exert a negative influence on maternal emotion after delivery, but this does not have strong correlation with child development evaluated by mothers.

Objectives We examined the socio-demographic and behavioral factors associated with alcohol consumption before and after pregnancy awareness in pregnant women. Methods This cross-sectional study included 91,828 pregnant women in a nationwide Japanese birth cohort study from 2011 to 2014. Alcohol consumption before and after pregnancy awareness, and sociodemographic behavioral characteristics were assessed through self-reported questionnaires. Determinants of alcohol consumption were investigated using logistic regression. Results Prevalence of alcohol consumption before and after pregnancy awareness was 50.0% and 2.8%, respectively. Most women consumed low to moderate levels of alcohol. Before pregnancy awareness, high educational level (odds ratios [OR] 1.11, 95% confidence interval [CI] 1.07 to 1.15), high household income (OR 1.16, 95% CI 1.09 to 1.24), and smoking (OR 1.77, 95% CI 1.65 to 1.90) were significantly associated with increased odds of alcohol consumption. After pregnancy awareness, older age (OR 1.73, 95% CI 1.54 to 1.94) and smoking (OR 5.57, 95% CI 4.88 to 6.37) were significantly associated with increased odds of alcohol consumption, and high education level (OR 0.72, 95% CI 0.64 to 0.81) and high household income (OR 0.75, 95% CI 0.63 to 0.89) were significantly associated with decreased odds of alcohol consumption. Conclusion A half of women consumed alcohol before pregnancy awareness. Guidelines recommend abstinence from alcohol consumption in pregnant women for precaution, although influence of low to moderate levels of prenatal alcohol exposure on the fetus is inconclusive. Social-demographic characteristics differed between women who consumed alcohol before pregnancy awareness and women who continued alcohol after pregnancy awareness.

Background: Although there has been an increase in reports regarding the association between perinatal risk factors and mother-infant bonding, the results have been inconsistent.Methods: This is an ongoing cohort designed study to measure the effect of environmental factors on children's health with the use of data from the Japan Environment and Children's Study. We investigated mother-infant bonding at 1 year old according to parity and mode of delivery.Results: A total of 82,540 participants, including 36,662 primipara mothers and 45,878 multipara mothers, were analyzed in the present study. Exclusive breastfeeding, marriage, and non-working factors were higher in multipara mothers than in primipara mothers. The total Mother-to-Infant Bonding Scale Japanese version (MIBS-J) score was higher (worse) in primipara than multipara (mean total: 1.129 vs. 0.897, p < 0.001). Primipara mothers also had higher anger and rejection scores than multipara mothers. When we analyzed only multipara mothers without any history of previous Cesarean section (CS), MIBS-J scores were higher in Cesarean delivery mothers than vaginal delivery mothers (p = 0.038).Limitations: We used a self-reported bonding measure. Although a self-report measure is convenient and important, an observer rating may be less susceptible to bias in perception. We did not distinguish elective CS from emergency CS, which may have different influences on mother-infant bonding.Conclusions: Primipara mothers showed worse mother-infant bonding than multipara mothers, regardless of mode of delivery. Caesarian delivery itself appears to have little effect on mother-infant bonding.

Pregnancy intention is reported to be associated with the risk of postpartum depression (PPD), but the impact of feelings toward being pregnant on PPD is unknown. We aimed to examine whether feelings toward being pregnant are associated with PPD at 1 month after childbirth. In our nationwide study between 2011 and 2014 in Japan, we used multivariate logistic regression analyses to examine the associations between pregnancy intention and feelings toward being pregnant with PPD [Edinburgh Postnatal Depression Scale (EPDS score > 9 or > 12)] among Japanese women. Among 92,431 women, 14.0 and 5.4% had PPD with EPDS scores > 9 and > 12, respectively. Compared with women who felt very happy to be pregnant, those whose pregnancy was unintended but happy, unintended and confused, those who felt troubled, and those who felt no emotion toward being pregnant had increased risks of PPD [multivariable odds ratios (95% confidence intervals (CIs)) = 1.17 (1.11–1.22), 1.39 (1.29–1.49), 1.74 (1.42–2.14), and 1.58 (1.22–2.02), respectively, for EPDS score > 9]. Those associations were more evident without antenatal possible mental illness (K6 score < 13). Women whose pregnancy was unintended should be regarded as targets for the early detection and prevention of PPD irrespective of whether they felt happy or confused.

Background: Persistent pain during pregnancy is a significant health issue, which could be correlated with psychological distress resulting from inadequate social support. This study aims to investigate whether the relationship between poor social support and antenatal pain is mediated by psychological distress. We also aimed to examine whether social cohesion moderates the influence of psychological distress on the relationship between social support and antenatal pain. Methods: We analysed 94,517 pregnancies of women from a Japanese national birth cohort completed questionnaires assessing pain, psychological distress, social support and social cohesion. Psychological distress was assessed using the Kessler Psychological Distress Scale. Two types of models were used: the mediation model to examine whether the association between social support and pain was mediated by psychological distress the moderated mediation model to analyse whether social cohesion buffered the negative effect of inadequate social support on pain. Demographic, socioeconomic and psychological factors were controlled for in all analyses. Results: Psychological distress was fully mediated the association between social support and pain. Social cohesion had a focal moderation effect on the inverse association between social support and psychological distress (unstandardized regression coefficient [β] = 0.09 95% CI, 0.07–0.11) and functioned as moderator for the indirect effect of social support on antenatal pain (index of moderated mediation = 0.006 95% CI, 0.004–0.007). Conclusions: Poor social support was related to antenatal pain through psychological distress, possibly buffered by social cohesion. During the antenatal period, social support and cohesion are important for women. Significance: In this study, poor social support was found to be associated with pain intensity during pregnancy, which was mediated by psychological distress and might be buffered by desirable social cohesion. This finding could potentially help healthcare providers and policy makers to understand the importance of desirable social cohesion in preventing pain among pregnant women.

Contact with companion animals has been suggested to have important roles in enhancing child development. However, studies focused on child development and pet ownership at a very early age are limited. The purpose of the current study was to investigate child development in relation to pet ownership at an early age in a nationwide prospective birth cohort study: the Japan Environment and Children's Study. Associations between cat and dog ownership at six months and infant development at 12 months of age were examined in this study. Infant development was assessed using the Ages & Stages Questionnaires(TM) (ASQ-3) at 12 months. Among participants of (Japan Environment and Children's Study) JECS, those with available data of cat and dog ownership at six months and data for the ASQ-3 at 12 months were included (n = 78,868). Having dogs showed higher percentages of pass in all five domains measured by ASQ-3 (communication, gross motor, fine motor, problem-solving, and personal-social) compared to those who did not have dogs. Significantly decreased odds ratios (ORs) of developmental delays were observed in association with having dogs in all fix domains (communication: OR = 0.73, gross motor: OR = 0.86, fine motor: OR = 0.84, problem-solving: OR = 0.90, personal-social: OR = 0.83). This study suggested that early life dog ownership may reduce the risks of child developmental delays.

子どもで近年アレルギーや肥満が増加しているという報告がある。生体に存在する物質でバイオマーカーとなるものにはゲノムや染色体の変異や遺伝子の発現変異などが挙げられる。染色体の末端にあるテロメアと呼ばれるゲノム配列は、ヒトでは(TTAGGG)の繰り返し配列であり、2.5-15kbpからなる。体細胞では細胞分裂をするたびにテロメアの長さが短縮し、細胞は老化し増殖しなくなる。一方で生殖細胞や幹細胞、がん細胞ではテロメアーゼの働きによりテロメアは伸長し、細胞は増殖する。幼児期の飲料とテロメアの長さに関する報告(Janet MW. et al., 2016, 2017)があるが、胎児期におけるPCBとテロメア長に関する報告はまだない。そこで、我々はPCBがテロメア長に与える影響について調査した。 調査対象は千葉大学予防医学センターが行なっている「千葉こども調査」で収集された94組の母子である。テロメア長は臍帯組織から抽出されたゲノムDNAを用いqPCRで評価した(Toki F. et al., 2016)。PCB異性体は母親の末梢血では21異性体で、臍帯血については23異性体でGC-MSを用いて測定した。Spearmanの順位相関係数で解析を行った結果、主要な異性体のPCB74, 118, 153, 138, 187, 170についてはテロメア長とPCB異性体については男女共、男女別でも関連がなかった(P>0.05)。一方で、男女を合わせた解析では臍帯血のPCB99（ng/g -wet）（rho =0.240、P = 0.021）, 女子のみで臍帯血のPCB99（ng/g -wet）（rho =0.279、P = 0.043）については正の相関があった。PCB99についてはC57BL6 マウスの精子形成に関与することが分かっている。今後はさらにサンプル数を増やして調査する予定である。

ObjectiveFor several observational studies that have reported the factors related to gastroschisis, the target population in these studies was mainly residents of Europe or the US, and there is little data on the Asian population. In this study, we summarised characteristics of Japanese women who delivered infants with gastroschisis, particularly focusing on the pre-pregnancy body mass index (BMI), which was found to be inversely associated with gastroschisis in past studies, because the distribution of BMI is clearly different in Asia and the West.ResultsWe used data from a nationwide birth cohort study which recruited pregnant women between 2011 and 2014. Among 92,796 women who delivered singleton live births, the frequency of underweight (pre-pregnancy BMI<18.5 kg/m(2)) was 16.2%, reference weight (18.5-24.9 kg/m(2)) 73.1%, and overweight (<greater than or equal to>25.0 kg/m(2)) 10.6%. We identified only 9 infants with gastroschisis, 2 of whose women were underweight (frequency of gastroschisis=0.01%), 5 were in the reference group (0.01%), and 2 were overweight (0.02%). Of these 9 women, none were aged<20 years, 2 were aged 20-29 years (frequency=0.01%), and 7 were aged 30-39 years (0.01%). No reduction in the occurrence of gastroschisis was apparent among Japanese women who were overweight before pregnancy.

© 2020 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd Aims/Introduction: We aimed to evaluate the metabolic status of pregnant women by assessing metabolic biomarkers of participants in the Japan Environment and Children’s Study, a nationwide, multicenter, pregnancy and birth cohort. Materials and Methods: Pregnant women aged 14–50 years were studied in 15 centers across Japan. Clinical information was obtained using self-administered questionnaires. Blood samples were taken during the first two trimesters to measure metabolic biomarkers. Samples were divided into seven groups according to the weeks of pregnancy. Results: Among 82,972 pregnant women, 43 had only type 1 diabetes, 78 had only type 2 diabetes, 2,315 had only gestational diabetes and 354 had only dyslipidemia. Glycated hemoglobin, total cholesterol, low-density lipoprotein cholesterol and triglyceride across all the percentiles increased as prepregnancy body mass index increased, whereas high-density lipoprotein cholesterol levels across all the percentiles decreased as body mass index increased. Glycated hemoglobin was high in participants with type 1 diabetes or type 2 diabetes only, but not in those with gestational diabetes or hyperlipidemia only. Participants with type 2 diabetes or dyslipidemia only had high triglyceride in the first trimester, which then decreased in the second trimester. Participants with type 2 diabetes only also showed low high-density lipoprotein cholesterol, whereas participants with dyslipidemia only showed high total cholesterol and low-density lipoprotein cholesterol throughout. Conclusions: Metabolic biomarkers were affected by blood sample timing and underlying metabolic disease. The Japan Environment and Children’s Study will clarify the influences of metabolic status during pregnancy on the health and development of the offspring in future studies.

© 2019 The Author(s). Background: Cleft lip and/or palate is among the most prevalent congenital birth defects, and negatively affects maternal psychological status and may consequently result in higher prevalence of child maltreatment. However, the association of childbirths of infants with cleft lip and/or palate with maternal emotional involvement still remains unclear. We examined the association between childbirths of infants with cleft lip and/or palate and mother-to-infant bonding, using data from the Japan Environment and Children's Study, a nationwide birth cohort study. Methods: A cross-sectional study using the jecs-an-20,180,131 dataset was performed. A total 104,065 fetuses in 15 regional centres in Japan were enrolled after obtaining informed written consent. The Mother-to-Infant Bonding Scale, a self-report scale consisting of 10 items, was used to evaluate maternal bonding at one year after childbirth. Finally, the participants consisted of 79,140 mother-infant pairs, of which 211 mothers of infants with cleft lip and/or palate were included in our analyses. Multivariable logistic regression analysis using multiple imputation for missing data was performed to calculate the odds ratio and 95% confidence interval in the estimation of the association between bonding disorders and childbirths with cleft lip and/or palate. Results: No increased risk of bonding disorders was observed among all the mothers of infants with cleft lip and/or palate (odds ratio [95% confidence interval]; 0.97 [0.63-1.48], p = 0.880), however, advanced maternal age or multiple parity may adversely affect the associations between bonding disorders and cleft lip and/or palate, respectively. After stratification with a combination of maternal age and parity, a significant association of cleft lip and/or palate with bonding disorders was found only among advanced-age multiparae (odds ratio [95% confidence interval] = 2.51 [1.17-5.37], p = 0.018), but it was weakened after additional adjustment for maternal depression. Conclusions: Childbirths of infants with cleft lip and/or palate may increase the risk of bonding disorders among advanced-age multiparae, possibly through maternal depression. This finding provides valuable information for the provision of multidisciplinary cleft care.

BACKGROUND: With the aim to prevent sick building syndrome and worsening of allergic symptoms, primarily resulting from the indoor environment, the relationships among people's residential environment in recent years, their lifestyle habits, their awareness, and their symptoms were investigated using an online survey. METHODS: In the survey, respondents experiencing symptoms specific to sick building syndrome, although they were not diagnosed with sick building syndrome, were categorized in the pre-sick building syndrome group. The relationships among individual characteristics, residential environment, and individual awareness were analyzed. RESULTS: Results showed that the prevalence of pre-sick building syndrome was high among young (aged 20-29 years) population of both sexes. In addition, "condensation," "moisture," "musty odors" in the house, and the "use of deodorant and fragrance" were all significantly associated with pre-sick building syndrome. Conversely, there was no significant association with recently built "wooden" houses that are highly airtight and have thermal insulation. CONCLUSIONS: Efficient "ventilation" plans and "ventilation" improvement and air conditioning systems to prevent mold and condensation in rooms are necessary to maintain a good, indoor environment that is beneficial for health. Efforts should also be made to encourage individuals to regularly clean and effectively ventilate their homes.

Background: Gestational diabetes mellitus (GDM) has serious effects on both mother and child. Like Type 2 Diabetes Mellitus, it is increasing in prevalence world-wide. In addition to obesity, sleep duration has been named an important risk factor. Using a large cohort study, including data from 48,787 participants of the Japan Environment and Children's Study (JECS), we examined the association between sleep duration and both random blood glucose levels and GDM rates during pregnancy.Methods: Random blood glucose levels were measured during pregnancy. GDM diagnosis was based on the results of 75 g oral glucose tolerance test. Additional anthropometric data was collected from questionnaires for statistical analysis.Results: Compared to mothers averaging 7 to < 10 h sleep (reference group), women receiving < 5 h or >= 10 h sleep exhibited significantly elevated random blood glucose levels. This was associated with an elevated risk for positive GDM screening (< 5 h sleep: OR 1.17 (0.96-1.44) p = 0.126; >= 10 h sleep: OR 1.13 (1.03-1.25) p = 0.006). Calculating the risk for GDM, women sleeping < 5 h or >= 10 h exhibited elevated risks of 1.31-fold and 1.21 respectively. However, this trend was not found to be significant.Conclusions: Sleep is a critical factor in glucose metabolism, with both abnormally long and short sleep duration increasing random blood glucose levels in pregnant women. Moreover, the risk for positive GDM screening increases significantly with elevated sleep, >= 10 h per night. These findings are promising because they support the idea that sleep duration is a modifiable risk factor, and can be focused upon to improve health and pregnancy outcome.

BackgroundLower socioeconomic status is often thought to be associated with an elevated risk of postpartum depression; however, this relationship exhibits noticeable heterogeneity between studies. The present study examined this relationship in Japan.MethodsData were obtained from 90,194 mothers in an ongoing birth cohort of the Japan Environment and Children's Study. Socioeconomic status was assessed based on the mothers' highest education level during pregnancy. Postpartum depression was identified at 1 and 6months postpartum based on an Edinburgh Postnatal Depression Scale score of >= 9, and analyses were also performed based on the sub-scores for anxiety, depression, and anhedonia symptoms. Logistic and generalized linear regression model analyses were used to calculate odds ratios for postpartum depression according to education level with the highest education group (>= 16years of education) defined as the reference group, while controlling for covariates in a stepwise fashion.ResultsUnivariate analysis revealed that a lower education level was associated with a higher prevalence of postpartum depression and related symptoms. Although these relationships weakened in the fully adjusted models, odds ratios for cases and related symptoms remained significant at 1 and 6months postpartum. Among three symptom dimensions, the relationship was strongest and weakest in the depressive and anxiety symptoms, respectively.ConclusionsA lower education level was an independent risk factor for postpartum depression. In view of the low mobility of the education level, this finding suggests the potential importance of collecting information regarding education levels at the earliest opportunity.