Background: Reproductive history has been addressed as a risk factor for cardiovascular disease (CVD). We examined the relationship between reproductive history and CVD mortality in Japanese women. Methods: We followed 53,836 women without previous CVD or cancer history from 1988-1990 to 2009 in a prospective cohort study. Hazard ratios (HRs) and 95% confidence intervals (CIs) of CVD mortality were estimated according to the number of deliveries and maternal age at first delivery. Results: During the follow-up, 2,982 CVD-related deaths were identified. There was U-shaped association between the number of deliveries and risk of CVD mortality with reference to three deliveries, although the excess risk of CVD mortality associated with ≥5 deliveries was of borderline statistical significance. The corresponding multivariable HRs were 1.33 (95% CI, 1.12-1.58) and 1.11 (95% CI, 0.99-1.24). In addition, higher CVD mortality was associated with maternal age ≥28 years at first delivery than maternal age of 24-27 years at first delivery. The multivariable HRs were 1.22 (95% CI, 1.10-1.36) for 28-31 years at first delivery and 1.26 (95% CI, 1.04-1.52) for ≥32 years at first delivery. Moreover, among women with ≥3 deliveries, maternal age ≥28 years at first delivery was associated with 1.2-to 1.5-fold increased CVD mortality. Conclusion: The number of deliveries showed a U-shaped association with risk of CVD mortality. Higher maternal age at first delivery was associated with an increased risk of CVD mortality, and excessive risk in women aged ≥28 years at first delivery was noted in those with ≥3 deliveries.

Aim: To evaluate the pregnancy outcomes of preterm premature rupture of membranes (preterm PROM; PPROM) by gestational age. Methods: This cohort study analyzed data from the Japan Environment and Children's Study. Pregnancy outcomes were documented using descriptive statistics. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of complications. Results: Data were collected for 104 062 fetuses, and 99 776 were eligible for inclusion. The incidences of early (18-23 weeks) and late (24-36 weeks) PPROM were 0.1% (n = 102) and 1.2% (n = 1205), respectively. Of the 1307 cases, 66 (5.0%) resulted in miscarriage or stillbirth. Overall, 85.6% (1119/1307) resulted in preterm births, and 9.3% (122/1307) in term births. There was a higher incidence of oligohydramnios (OR 6.82,

This study aimed to evaluate the association of neonatal transfer with the risk of neurodevelopmental outcomes at 3 years of age. Data were obtained from the Japan Environment and Children’s Study. A general population of 103,060 pregnancies with 104,062 fetuses was enrolled in the study in 15 Regional Centers between January 2011 and March 2014. Live-born singletons at various gestational ages, including term infants, without congenital anomalies who were followed up until 3 years were included. Neurodevelopmental impairment was assessed using the Ages and Stages Questionnaire, third edition (ASQ-3) at 3 years of age. Logistic regression was used to estimate the adjusted risk and 95% confidence interval (CI) for newborns with neonatal transfer. Socioeconomic and perinatal factors were included as potential confounders in the analysis. Among 83,855 live-born singletons without congenital anomalies, 65,710 children were studied. Among them, 2780 (4.2%) were transferred in the neonatal period. After adjustment for potential confounders, the incidence of neurodevelopmental impairment (scores below the cut-off value of all 5 domains in the ASQ-3) was higher in children with neonatal transfer compared with those without neonatal transfer (communication: 6.5% vs 3.5%, OR 1.42, 95% CI 1.19–1.70; gross motor: 7.6% vs 4.0%, OR 1.26, 95% CI 1.07–1.49; fine motor: 11.3% vs 7.1%, OR 1.19, 95% CI 1.03–1.36; problem solving: 10.8% vs 6.8%, OR 1.29, 95% CI 1.12–1.48; and personal-social: 6.2% vs 2.9%, OR 1.52, 95% CI 1.26–1.83).   Conclusion: Neonatal transfer was associated with a higher risk of neurodevelopmental impairment at 3 years of age. What is Known:• Neonatal transfer after birth in preterm infants is associated with adverse short-term outcomes.• Long-term outcomes of outborn infants with neonatal transfer in the general population remain unclear. What is New:• This study suggests that neonatal transfer at birth is associated with an increased risk of neurodevelopmental impairment.• Efforts for referring high-risk pregnant women to higher level centers may reduce the incidence of neonatal transfer, leading to improved neurological outcomes in the general population.

<b><i>Introduction:</i></b> Currently, the association between the duration of neonatal phototherapy and the risk of allergic disorders has not been reported. This observational cohort study aimed to examine the association between allergic disorders, including food allergies, that are present before 3 years of age and the duration of phototherapy using the nationwide birth cohort data. <b><i>Methods:</i></b> The Japan Environment and Children’s Study was a nationwide birth cohort study. Data of 77,064 infants aged 1 year, 1.5 years, 2 years, and 3 years were analyzed. We divided the participants into three groups: no phototherapy, short phototherapy (1–24 h), and long phototherapy (&#x3e;24 h) and evaluated the cumulative incidence of allergic disorders before 3 years of age, including asthma, atopic dermatitis, and food allergies. Logistic regression analysis was performed to assess the impact of phototherapy duration on the cumulative incidence of allergic disorders. <b><i>Results:</i></b> After adjustment for potential risk factors, long phototherapy was found to be positively associated with food allergies at age 2 years (OR: 1.16; 95% CI: 1.01–1.33) and all allergic disorders at age 3 years (OR: 1.12; 95% CI: 1.01–1.24), including food allergies (OR 1.18; 95% CI: 1.04–1.35). <b><i>Conclusion:</i></b> A long duration of neonatal phototherapy was positively associated with the risk of allergic disorders, especially food allergies.