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Tsuyoshi Murata

and 12 more

Objective: To evaluate the association between maternal pre-pregnancy body mass index and fetal acidosis while accounting for the mode of delivery. Design: Prospective cohort study Setting: Japan Population: Participants from the Japan Environment and Children’s Study with singleton pregnancies after 22 weeks of gestation who gave birth during 2011–2014 Methods: Participants were categorized into five groups according to pre-pregnancy body mass index (BMI) (kg/m2): G1 (BMI<18.5), G2 (18.5 to <20.0), G3 (20.0 to <23.0), G4 (23.0 to <25.0), and G5 (≥25.0). Multiple logistic regression analysis evaluated the effect of maternal pre-pregnancy BMI on fetal acidosis while accounting for the mode of delivery. Main outcome measures: Fetal acidosis was defined as umbilical artery pH (UmA-pH) <7.2 or <7.1. Results: We analyzed 71,799 participants. Adjusted odds ratios (aORs) of UmA-pH <7.2 using G3 as the reference group were 1.17 (95% confidence interval [CI], 1.06–1.30) in G5 and 0.89 (95% CI, 0.82–0.97) in G2. After stratification, aORs of UmA-pH <7.2 were 1.12 (95% CI, 1.08–1.35) in G5 and 0.90 (95% CI, 0.83–0.98) in G2, and the aOR of UmA-pH <7.1 was 0.80 (95% CI, 0.65–0.98) in G2 using G3 as the reference group for vaginal delivery. No association existed between pre-pregnancy BMI and fetal acidosis for delivery via cesarean section. Conclusions: In Japanese women, pre-pregnancy BMI ≥25.0 kg/m2 significantly increased the likelihood of fetal acidosis in newborns delivered vaginally.

Tsuyoshi Murata

and 13 more

Objective: To evaluate the incidence of adverse pregnancy outcomes (APOs) in women with uterine myomas and clarify the effect of uterine myomas on pregnancy outcomes. Design: Prospective cohort study Setting: The Japan Environment and Children’s Study (between 2011–2014) Population: Women (86,370) with singleton births after 22 weeks of gestation. Methods: Using logistic regression, the adjusted odds ratios (aORs) for APOs were calculated considering women without uterine myomas as the reference. Additionally, we used logistic regression to evaluate the effect of intrauterine infection (II) on the incidence of preterm births (PTB) and preterm premature rupture of membranes (pPROM). Main Outcome Measures: PTB (before 37 and 34 weeks), pPROM, II, and gestational hypertension (GH). Results: In women with uterine myomas, the aORs for PTB before 37 and 34 weeks, pPROM, II, and GH were 1.37 (95% confidence interval [CI], 1.22–1.54), 1.61 (95% CI, 1.27–2.05), 1.65 (95% CI, 1.33–2.04), 1.05 (95% CI, 0.75–1.46), and 1.20 (95% CI, 1.05–1.38), respectively. In women with both uterine myomas and intrauterine infection, the aORs for PTB before 37 weeks and pPROM were not significantly increased. Conclusions: Intra-pregnancy uterine myomas were associated with an increased risk of APOs. II in women with uterine myomas was not associated with PTB or pPROM. These data suggest a potential mechanical disadvantage in pregnant women with uterine myomas. Funding: Ministry of the Environment, Japan Key words: uterine myoma, preterm birth, preterm premature rupture of membrane, intrauterine infection

Tsuyoshi Murata

and 13 more

Background: The effects of maternal ritodrine hydrochloride administration (MRA) during pregnancy on fetuses and offspring are not entirely clear. The present study aimed to evaluate the association between MRA and childhood wheezing using data from a nationwide Japanese birth cohort study. Methods: This study retrospectively analyzed data from the Japan Environment and Children’s Study, a nationwide birth cohort study, conducted between 2011 and 2014. Data of women with singleton births after 22 weeks of gestation were analyzed. The participants were divided according to MRA status. Considering childhood factors affecting the incidence of wheezing, a logistic regression model was used to calculate adjusted odds ratios for “wheezing ever,” diagnosis of asthma in the last 12 months, and “asthma ever” in women with MRA, with women who did not receive MRA as the reference. Participants were stratified by term births, and adjusted odds ratios for outcomes were calculated using a logistic regression model. Results: A total of 68,123 participants were analyzed. The adjusted odds ratio for wheezing ever was 1.17 (95% confidence interval, 1.12–1.22). The adjusted odds ratios for the other outcomes did not significantly increase after adjusting for childhood factors. The same tendency was confirmed after excluding women with preterm births. Conclusion: MRA was associated with an increased incidence of childhood wheezing up to three years, irrespective of term births or preterm births. It is important that perinatal physicians consider both the adverse maternal side effects of MRA and its potential effects on the offspring’s childhood.

Tsuyoshi Murata

and 14 more

Background: This study aimed to evaluate differences in maternal characteristics and obstetric and childhood outcomes between term births according to the use of tocolytic treatment. Methods: This study analyzed the data of the participants enrolled in the Japan Environment and Children’s Study between 2011 and 2014. Data of 63,409 women with singleton births after 37 weeks of gestation were analyzed. We compared maternal characteristics, obstetric outcomes, and childhood outcomes between term births with tocolytic treatment and those without tocolytic treatment. Multiple logistic regression was used to calculate adjusted odds ratios for childhood outcomes with significant between-group differences in the univariable analysis for term births with tocolytic agents, with term births without tocolytic agents as the reference group. Results: In term births with tocolytic agents, participants had significantly younger age, leaner body mass index, higher oxidative stress during pregnancy, shorter pregnancy period, lighter neonatal birth weight, lower incidence of gestational diabetes mellitus, higher incidence of preterm premature rupture of membrane, higher rates of cesarean section, lower incidence of meconium-stained amniotic fluid during pregnancy, and higher incidence of childhood allergic disorders. The incidence of childhood developmental disorders showed no significant between-group differences. The adjusted odds ratio for childhood allergic disorders in term births with tocolytic agents was 1.09 (95% confidence interval, 1.04-1.14). Conclusions: This study found no significant association between tocolytic treatment and the incidence of childhood developmental disorders in children with term births. However, tocolytic treatment showed an association with a slightly increased incidence of childhood allergic disorders.

Hyo Kyozuka

and 13 more

Objective: To examine the effect of maternal age on placental abruption Design: Prospective cohort study Setting: Fifteen regional centers across Japan Population: We identified 94,410 Japanese women (93,994 without placental abruption and 416 with placental abruption) who were recruited in the Japan Environment and Children’s study between January 2011 and March 2014. Methods: Multiple regression models were used to identify whether maternal age (<20 years, 20–24 years, 25–29 years, 30–34 years, and ≥ 35 years) is a risk factor for placental abruption. The analyses were conducted while considering history of placental abruption, assisted reproductive technology, number of previous deliveries, smoking during pregnancy, body mass index before pregnancy, chronic hypertension, and uterine myoma as confounding factors. Main outcome measures: Maternal age as a risk factor for placental abruption Results: Besides advanced maternal age (≥35 years; adjusted odds ratio [aOR]: 1.7, 95% confidence interval [CI]: 1.1–2.5), teenage pregnancy was also a risk factor for placental abruption (aOR: 2.8, 95% CI: 1.2–6.5) when maternal age of 20–24 years was set as a reference. Conclusions: In the Japanese general population, besides advanced maternal age, teenage pregnancy was also a strong risk factor for placental abruption. The maternal age in Japan is changing since recent decades. Therefore, it is important for obstetric care providers to provide proper counseling to young women based on the up-to-date evidences. Funding: The Japan Environment and Children’s Study was funded by the Ministry of the Environment, Japan

Tsuyoshi Murata

and 13 more

Objective: To evaluate the effect of maternal sleep duration (MSD) on low birth weight infants (LBW), small for gestational age infants (SGA), and macrosomia. Design: Prospective cohort study Setting: The Japan Environment and Children’s Study (JECS) Population: Participants enrolled in JECS, with singleton pregnancies after 22 weeks, who gave birth between 2011 and 2014. Methods: Participants were categorized into five groups according to MSD during pregnancy: G1 (MSD <6.0 h), G2 (6.0–7.9 h), G3 (8.0–8.9 h), G4 (9.0–9.9 h), and G5 (10.0–12.0 h). Main outcome measures: The effect of MSD on the risk of LBW (<2,500 g and <1,500 g), SGA, and macrosomia (>4,000 g) with G2 as the reference, while adjusting for gestational excessive body weight gain (BWG). Analysis was also performed after stratification by gestational BWG. Results: We analyzed 82,171 participants. The adjusted odds ratios (aORs) of LBW <2,500 g in G4 and G5 and of SGA in G4 were 0.90 (95% confidence interval [CI], 0.83-0.99), 0.86 (95% CI, 0.76-0.99), and 0.91 (95% CI, 0.82-0.99), respectively, before adjusting for excessive gestational BWG. No significant association was observed between MSD and these outcomes after adjusting for excessive gestational BWG. Among women with appropriate gestational BWG, the aORs of LBW <2,500 g and SGA in G4 were 0.88 (95% CI, 0.80-0.97) and 0.87 (95% CI, 0.78-0.97), respectively. Conclusion: This study revealed that 9.0–9.9 h of MSD significantly decreased LBW <2,500 g and SGA in pregnant women with appropriate gestational BWG, relative to 6.0–7.9 h of MSD.

Hyo Kyozuka

and 13 more