Gestational Age and Neurodevelopmental Delay in Term Births at 6 and 12 Months: The Japan Environment and Children's Study (JECS).

BACKGROUND: In the recent years, a high risk of developmental delay not only in very low birth weight infants and late preterm infants but also in early term infants (37-38 weeks) have increasingly been reported. However, in Japan, there are virtually no studies regarding the development delays in early term infants. METHODS: This study used the data from the Japan Environment and Children's Study (JECS), a birth cohort study conducted in Japan. Data were selected for analysis from the records of 104,065 fetal records. The risk of neurodevelopmental delays at 6 months and 12 months after birth was evaluated using multivariate analysis for infants of various gestational ages, using the 40th week of pregnancy as a reference value. Neurodevelopment was evaluated at 6 months and 12 months after birth using the Ages and Stages Questionnaires, Japanese translation (J-ASQ-3). RESULTS: The proportion of infants born at a gestational age of 37 to 38 weeks who did not reach the J-ASQ-3 score cutoff value was significantly higher in all areas at both 6 months and 12 months after birth, when compared to that of infants born at 40 weeks. The odds ratio decreased at 12 months after birth compared to that at 6 months after birth. CONCLUSION: Early term infants in Japan are at an increased risk of neurodevelopmental delay at 12 months after birth.

Association of Chlamydia trachomatis infection with pregnancy outcomes among Japanese pregnant women: The Japan environment and children's study.

This study aimed to investigate the impact of Chlamydia trachomatis (CT) infection on pregnancy outcome in pregnant Japanese women. We utilized the data from a nationwide birth cohort study, the Japan Environment and Children's Study (JECS), for this study. We enrolled 26,385 individuals who could refer to data on pregnancy outcomes and confounding factors, with data on CT. Binominal logistic regression models were used to determine whether pregnant women with CT positivity were at more risk of experiencing adverse pregnancy outcomes, preterm birth (PTB), preterm prelabor rupture of membrane (pPROM), low birth weight (LBW) infants, small for gestational age (SGA) births, or hypertensive disorders of pregnancy (HDP). After adjusting for maternal age, parity, marital status, smoking status, and education status, there were no significantly increased risks of PTB, pPROM, LBW infants, SGA, and HDP in the odds ratios. No significant increase in the risk of adverse pregnancy outcomes was observed in any of the subgroup analyses, which were limited to the pregnancy women in Fukushima prefecture, where CT screening could be confirmed at 28-30 weeks of gestation. We believe that the results of this study will make a significant contribution to the future of medical care for pregnant women in Japan. Our findings are important for medical practitioners to contribute to the future medical treatment of Japanese pregnant women, and also to contribute to pre-conception care for Japanese society as a whole, including pregnant women.

Maternal hemoglobin levels and neonatal outcomes: the Japan Environment and Children's Study.

BACKGROUND: Low birth weight (LBW), small for gestational age (SGA), and preterm birth (PTB) are important neonatal outcomes that may affect infant morbidity and mortality. The aim of this study is to investigate associations between maternal hemoglobin (Hb) concentrations and pregnancy outcomes of LBW, SGA, and PTB. METHODS: This was a prospective birth cohort study using data of the Japan Environment and Children's Study. Participants were divided into five groups according to maternal Hb (g/dL) in the first and second trimesters: group 1, Hb < 9; group 2, 9 ≤ Hb < 11.0; group 3, 11.0 ≤ Hb < 13.0; group 4, 13.0 < Hb < 14.0; and group 5, 14.0 ≤ Hb. We examined the relationships between LBW, PTB, SGA, and maternal Hb in the first and second trimesters. RESULTS: Excluding 29,673, a total of 74,392 newborns (first trimester: n = 39,084, second trimester: n = 35,308) were included. We obtained adjusted odds ratios (aORs) (95% confidence intervals (CIs)) using multivariate analysis; compared with group 3 in the first trimesters, women in group 1 were at increased risk of PTB (aOR, 3.20; 95% CI, 1.69-6.09), LBW (aOR, 2.21; 95% CI, 1.19-4.09). In the second trimester, multivariate analysis revealed that, compared with group 3 in the second trimester, women in group 1 were at increased risk of PTB (aOR, 2.30; 95% CI, 1.19-4.42) and women in group 5 were at increased risk of LBW (aOR, 1.87; 95% CI, 1.24-2.81) and PTB (aOR, 1.73; 95% CI, 1.06-2.83). CONCLUSIONS: Elevated maternal Hb in the second trimester was associated with risks of PTB and LBW.

Prepregnancy antiinflammatory diet in pregnant women with endometriosis: The Japan Environment and Children's Study.

OBJECTIVES: Increased risk of preterm birth (PTB) in women with endometriosis is considered to be associated with chronic inflammatory conditions. Accordingly, we hypothesized that a prepregnancy antiinflammatory diet is a potential form of preconception care for preventing PTB in women with endometriosis and conducted this study to investigate the correlation of a prepregnancy antiinflammatory diet with obstetric outcomes in this patient population. METHODS: We used singleton pregnancy data from the Japan Environment and Children's Study involving live births from 2011 to 2014. Individual meal patterns before pregnancy, derived through food frequency questionnaires, were used to calculate the Dietary Inflammatory Index. Participants were categorized according to Dietary Inflammatory Index quintiles (Q1 and Q5 were the most proinflammatory and antiinflammatory groups, respectively), and a multiple logistic regression model was used to estimate the effect of the antiinflammatory diet on PTB before 37 or 34 wk and on low birth weight (LBW) <2500 or 1500 g. RESULTS: In women who did not undergo assisted reproduction, significantly reduced risk was found in the Q5 group for both PTB at <34 wk significantly decreased (adjusted odds ratio, 0.25; 95% confidence interval, 0.07-0.83) and low birth weight <1500 g (adjusted odds ratio, 0.07; 95% confidence interval, 0.01-0.60). CONCLUSIONS: This study suggests a distinct effect of an antiinflammatory diet on more severe obstetric outcomes, specifically PTB before 34 wk and low birth weight <1500 g, for women with endometriosis. Preconception lifestyle can improve perinatal mortality and morbidity among these women.

Gestational weight gain and risk factors for postpartum depression symptoms from the Japan Environment and Children's Study: a prospective cohort study.

BACKGROUND: The relationship between postpartum depression symptoms (PPDS) and gestational weight gain is controversial. We aimed to examine the risk of gestational weight gain for PPDS at 1 month postpartum based on the pre-pregnancy body mass index (BMI). METHODS: A prospective cohort study recruited 80 927 Japanese women 2011-2014. They categorized according to their pre-pregnancy BMI into group 1 (<18.5 kg/m2), group 2 (18.5 to <20.0 kg/m2), group 3 (20.0 to <23.0 kg/m2), group 4 (23.0 to <25.0 kg/m2), and group 5 (≧25.0 kg/m2). Multiple logistic regression analysis was performed for each BMI category to identify potential risk factors of insufficient or excessive gestational weight gain associated with PPDS, following adjustments for maternal age, education, annual household income, smoking, parity, mode of delivery, cessation of breast feeding, psychological stress, and daily energy intakes during pregnancy. RESULTS: Among participants in group 3, insufficient gestational weight gain was a risk factor for PPDS (adjusted odds ratio: 1.24, 95% confidence interval: 1.14-1.36). This result was not modified by intermediate factors. LIMITATIONS: The criteria of appropriate gestational weight gain were determined from the adverse pregnancy outcomes not validated for PPDS. Other confounding factors for PPDS like psychotic disorders were not examined. CONCLUSIONS: For women with a pre-pregnancy BMI between 20.0 and <23.0 kg/m2, insufficient gestational weight gain is a risk factor for PPDS. Therefore, monitoring gestational weight gain is recommended for the early detection of PPDS in these women.

Impact of preconception sodium intake on hypertensive disorders of pregnancy: The Japan Environment and Children's study.

OBJECTIVES: Determining the appropriate preconception care to reduce the occurrence of hypertensive disorders of pregnancy (HDP) remains a challenge in modern obstetrics. We aimed to examine the association between pre-pregnancy sodium (Na) intake and the development of HDP in normotensive women. STUDY DESIGN: From the Japan Environment and Children's study (JECS) database, we identified 85,152 normotensive Japanese women who were recruited to the JECS between January 2011 and March 2014. Participants were categorized into five groups according to pre-pregnancy Na intake quintiles (Q1 and Q5 were the lowest and highest Na intake groups, respectively). MAIN OUTCOME MEASURES: Multiple logistic regressions were performed to identify the effect of pre-pregnancy Na intake on HDP, early-onset (<34 weeks) HDP, late-onset (34 ≥ weeks) HDP, and HDP with/without small for gestational age (SGA). RESULTS: Using Q3 (the middle Na intake group) as the reference, multiple logistic regression showed that both the lowest (Q1) and highest (Q5) Na intake groups had an increased risk of HDP with SGA [adjusted odds ratio (aOR): 1.50, 95% confidence interval (CI): 1.02-2.21 and aOR: 1.52, 95% CI: 1.03-2.24, respectively]. CONCLUSIONS: Both lower and higher Na intake before pregnancy increases the risk of HDP with SGA in normotensive Japanese women. This finding may indicate new recommendations for Na intake before pregnancy to prevent HDP.

Antenatal and postnatal association of maternal bonding and mental health in Fukushima after the Great East Japan Earthquake of 2011:The Japan Environment and Children's Study (JECS).

BACKGROUND: Japan Environmental and Children's Study (JECS) was under way in Fukushima at the time of the triple disaster. It was initially to assess the effects of environmental factors on children's health, but given the situation particular to the accident, it could also offer an additional source of material with which to examine the psychological impacts of the disaster on mothers. This study aimed to examine the characteristics of mental health of Fukushima mothers after the triple disaster by comparing the scores in Fukushima with the nationwide scores. Then, it aimed to examine associations between their maternal bonding and mental health both during pregnancy and following birth. METHODS: The JECS administered the Kessler 6-item psychological distress scale (K6) during pregnancy and the Edinburgh Postnatal Depression Scale (EPDS) 1 month following birth to 97 454 eligible women. In conjunction with the JECS, this study analysed the scores of 11 630 women in Fukushima which were obtained in the JECS between 2011 and 2015, and compared them with the nationwide scores during the same time period. RESULTS: The proportion of mothers having 'negative feelings toward pregnancy' was significantly higher in Fukushima Regional centre (RC) than in the other 13 RCs between 2011 and 2014. No significant difference in the 'lack of affection' scores following birth was found between Fukushima RC and other RCs in 2012 and 2013, but the score in Fukushima RC was significantly lower in 2014 and 2015. The K6 scores in Fukushima RC were significantly higher than in other RCs in all years, and the EPDS scores following birth in Fukushima RC were also higher than in the 13 RCs in all years. The results of multivariate analysis showed a significant association between 'mothers' negative feelings toward pregnancy' and depressive symptoms, except in Fukushima RC in 2011. Also, it showed another significant association between 'lack of affection' and postpartum depressive symptoms from 2012 to 2015 in both Fukushima RC and 13 RCs. K6 scores during pregnancy were significantly associated with EPDS scores throughout the study period in both Fukushima RC and 13 RCs. LIMITATIONS: Due to the lack of information on participants' residential region at the municipal level in the JECS, it was unable to measure regional differences within Fukushima prefecture. CONCLUSION: This study shed light on the relationship between maternal bonding and mental health both during pregnancy and following birth by using the sequential and periodic national data sets. While showing the maternal characteristics associated with depressive symptoms during pregnancy and following birth in Japan, it distinguished the characteristics between Fukushima and nationwide. It raised the possibility that providing mothers in Fukushima with supports to increase their bonding toward their pregnancy could prevent the development of depressive tendency. The results could suggest that not only depression prevention measures but also maternal bonding support could be necessary in the region.

Dietary Inflammatory Index during Pregnancy and the Risk of Intrapartum Fetal Asphyxia: The Japan Environment and Children's Study.

We aimed to examine the impact of a daily pro-inflammatory diet during pregnancy on intrapartum fetal acidemia using a large birth cohort study in Japan. We used data on singleton pregnancies in the Japan Environment and Children's Study (JECS) involving births from 2011 to 2014 through vaginal delivery to calculate the maternal dietary inflammatory index (DII). Participants were categorized according to DII quintiles. A multiple logistic regression model was used to estimate the risk of a pro-inflammatory diet on fetal umbilical artery pH. In total, 56,490 participants were eligible for this study. Multiple regression analysis showed that nulliparous women who had undergone vaginal delivery and were consuming a pro-inflammatory diet had an increased risk of pH < 7.10 (adjusted odds ratio [aOR]: 1.64, 95% confidence interval [CI]: 1.12-2.39). Among these women, the risk of pH < 7.10 was not affected by the duration of labor (aOR: 1.64, 95% CI: 1.11-2.42). In conclusion, following a pro-inflammatory diet during pregnancy is a risk factor for fetal acidosis among nulliparous women undergoing vaginal delivery. A high DII diet during pregnancy may modify the intrapartum fetal heart rate pattern via intrauterine inflammation.

Association between pre-pregnancy calcium intake and hypertensive disorders during the first pregnancy: the Japan environment and children's study.

BACKGROUND: Determining the appropriate preconception care to reduce the occurrence of hypertensive disorder of pregnancy (HDP) remains a challenge in modern obstetrics. This study aimed to examine the association between pre-pregnancy calcium (Ca) intake and HDP in normotensive primiparas. METHODS: We used data from the Japan Environment Children's study (JECS), which is the largest birth cohort study. A total of 33,894 normotensive Japanese primiparas were recruited for JECS between January 2011 and March 2014. Participants were categorized into five groups according to pre-pregnancy Ca intake quintiles (Q1 and Q5 were the lowest and highest Ca intake groups, respectively) to compare their basic background and obstetrics outcome. Multiple logistic regressions were performed to identify the effect of pre-pregnancy Ca intake on HDP, early onset HDP, and late-onset HDP, using Ca intake thresholds of 500, 550, 650, 700, 1000, 1500, and 1500 mg. RESULTS: We found significant differences in maternal background among the Ca intake groups; in particular, there were more participants with low socioeconomic status, indicated by low education level and low household income, and smokers in the lowest Ca intake group. Multiple logistic regression did not show any significant difference with regard to HDP, early onset HDP, and late-onset HDP in each Ca intake threshold. CONCLUSIONS: Despite considerable recommendations concerning Ca intake for women of reproductive age, the present study indicates that pre-pregnancy Ca intake was not associated with an increased risk of new-onset hypertension among primiparas during pregnancy. Further studies examining the effect of other pre-pregnancy dietary factors on obstetric outcomes should be considered in the formulation of earlier preventive strategies for primiparas.

Risk of adverse obstetric outcomes in Japanese women with systemic lupus erythematosus: The Japan Environment and Children's Study.

Systemic lupus erythematosus, simply known as lupus, is associated with adverse obstetric outcomes. This study evaluated the incidence of preterm births (before 37 and 34 weeks), low birthweight infants (<2500 g and <1500 g), small-for-gestational age infants, preterm premature rupture of membranes, and gestational hypertension in mothers with lupus and compared them with those of the Japanese general population. Data from participants in the Japan Environment and Children's Study who gave birth between 2011 and 2014 were collected. Only participants with singleton pregnancies were included. Adjusted odds ratios for the variables were calculated using a logistic regression model, with a general population as the reference. In total, 88,017 participants were included in the analysis, and 63 of them had lupus. The adjusted odds ratios of preterm births before 37 and 34 weeks, low birthweight infants <2500 g and <1500 g, small-for-gestational age infants, and preterm premature rupture of membranes in the systemic lupus erythematosus group were 8.1 (95% CI, 4.7-14.1), 5.2 (1.6-16.5), 6.5 (3.9-10.8), 5.4 (1.3-22.4), 2.9 (1.4-5.9), and 12.1 (5.7-25.5), respectively. The adjusted odds ratio of gestational hypertension was 1.4 (0.4-4.5). This study revealed increased risk of preterm births, low birthweight infants, small-for-gestational age infants, and preterm premature rupture of membranes in patients with lupus when compared with those in the general population.