Maternal magnesium intake and childhood wheezing in offspring at 3 years of age: the Japan Environment and Children's Study.

This study evaluated the association between maternal magnesium intake (MMI) and childhood wheezing incidence in 3-year-old offspring. We hypothesised that higher MMI imparts anti-inflammatory and antioxidant effects that decrease childhood wheezing incidence in offspring. Data of 79 907 women (singleton pregnancy, ≥ 22 weeks) from the Japan Environment and Children's Study (enrolled between 2011 and 2014) were analysed. Participants were categorised into quintiles of MMI (< 148·00, 148·00-187·99, 188·00-228·99, 229·00-289·99 and ≥ 290·00 mg/d), quintiles of adjusted MMI for daily energy intake (aMMI) (< 0·107, 0·107-0·119, 0·120-0·132, 0·133-0·149 and ≥ 0·150 mg/kcal) and MMI levels either below or above the ideal value (< 310·00 or ≥ 310·00 mg/d). Multivariable logistic regression analysis was performed to calculate OR for the incidence of childhood wheezing in offspring among participants in each MMI category, with the lowest MMI group considered the reference group. Maternal demographic, socio-economic, medical and other nutrient intake backgrounds were considered potential confounding factors. The adjusted OR (aOR) for childhood wheezing in the offspring of women with the highest MMI was 1·09 (95 % CI, 1·00, 1·20), whereas that calculated based on aMMI categories and offspring of women with above-ideal MMI levels remained unchanged. The highest MMI was associated with slightly increased childhood wheezing incidence in the offspring. MMI during pregnancy had an insignificant clinical impact on this incidence; moreover, modifying MMI would not significantly improve childhood wheezing incidence in offspring. Therefore, further studies should clarify the association between other prenatal factors and childhood wheezing incidence in offspring.

Tobacco Exposure During Pregnancy and Infections in Infants up to 1 Year of Age: The Japan Environment and Children's Study.

BACKGROUND: Tobacco exposure during pregnancy is associated with several adverse outcomes in infants. We investigated the association between tobacco exposure during pregnancy (both active and second-hand) and various infections in infants up to 1 year. METHODS: This prospective cohort study used a fixed dataset (jecs-an-20180131) from the Japan Environment and Children's Study of registered births in Japan during 2011-2014 that included 104,065 fetal records from enrolled pregnant women. Based on the participants' responses to the questionnaire on smoking status, mothers were first divided into "never smoked," "quit smoking," and "current smoker" groups and then into "no second-hand smoking (SHS)" and "SHS" groups. Infectious diseases included central nervous system infection, otitis media (OM), upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI), gastroenteritis (GI), and urinary tract infection. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated using logistic regression analysis and adjusted for maternal, socioeconomic, and postnatal confounding factors. RESULTS: Among the 73,205 newborns enrolled, multivariable analysis revealed that the aOR of LRTI and GI was 1.20 (95% CI, 1.07-1.33) and 1.18 (95% CI, 1.04-1.35), respectively, for the "current smoker with/without SHS" group compared with the "never smoked without SHS" group. "Quit smoking without SHS" was not associated with the risk of LRTI. SHS was associated with an increased risk of OM, URTI, LRTI, and GI, especially with LRTI and GI. CONCLUSION: Exposure to tobacco smoke during pregnancy was associated with an increased risk of OM, URTI, LRTI, and GI in infants during their first year of life.

Cord blood triglyceride and total cholesterol in preterm and term neonates: reference values and associated factors from the Japan Environment and Children's Study.

This study aimed to investigate the associations between cord serum total cholesterol (TC) and triglyceride (TG)levels and perinatal factors and determine the reference levels of cord blood TC and TG in Japanese neonates. This was a prospective birth cohort study using data from the Japan Environment and Children's Study, which included data on births from 2011 to 2014 in Japan. TC and TG levels were determined in cord blood samples. A total of 70,535 pairs of neonates (male: 36,001, female: 34,524) and mothers were included. The mean cord blood TC and TG levels were 72.2 mg/dL and 24.4 mg/dL, respectively. Multiple regression analyses revealed that gestational age and birth weight were significantly associated with cord blood TC (coefficient -2.35, 95% confidence interval [CI] -2.40 - -2.22 and coefficient 0.002, 95% CI 0.002-0.003, respectively) and TG (coefficient 3.09, 95% CI 3.01-3.17 and coefficient - 0.009, 95% CI - 0.009-0.008, respectively) levels. Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories.    Conclusion: Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term. Furthermore, the mean cord blood TC and TG levels decreased over the entire range of birth weight categories in Japanese newborns. Maternal complications such as maternal parity, HDP, PROM, maternal obesity and income level were associated with cord TC and TG levels. What is Known: • No studies have ascertained the reference levels of cord blood lipid levels in Japan. What is New: • Mean cord blood TG and TC levels decreased over the preterm period; however, these parameters increased during the term.

Association of Maternal Asthma and Total Serum Immunoglobulin E levels with Obstetric Complications: The Japan Environment and Children's Study.

OBJECTIVE: To evaluate the association between maternal asthma (MA) and obstetric complications, while considering subdivided total serum immunoglobulin E (IgE) levels. METHODS: Data of the participants enrolled in the Japan Environment and Children's Study between 2011 and 2014 were analyzed. In total, 77,131 women with singleton live births at and after 22 weeks of gestation were included. MA was defined based on a self-administered questionnaire. Women with MA were stratified based on the quartile of total serum IgE levels during pregnancy as follows: low IgE levels (< 52.40 IU/mL), moderate IgE levels (52.40-331.00 IU/mL), and high IgE levels (> 331.00 IU/mL). The adjusted odds ratios (aORs) for preterm births (PTB), small for gestational age (SGA) infants, gestational diabetes mellitus, and hypertensive disorders of pregnancy (HDP) were calculated using multivariable logistic regression, while considering women without MA as reference and maternal socioeconomic factors as confounders. RESULTS: The aORs for SGA infants and HDP in women with MA and high total serum IgE levels were 1.26 (95% confidence interval [CI], 1.05-1.50) and 1.33 (95% CI, 1.06-1.66), respectively. The aOR for SGA infants among women with MA and moderate total serum IgE levels was 0.85 (95% CI, 0.73-0.99). The aOR for PTB among women with MA and low total serum IgE levels was 1.26 (95% CI, 1.04-1.52). CONCLUSIONS FOR PRACTICE: MA with subdivided total serum IgE levels was associated with obstetric complications. Total serum IgE level may be a potential prognostic marker to predict obstetric complications in pregnancies with MA.

What is Already Known on this Subject? Maternal asthma (MA) is associated with several obstetric complications, including preterm births (PTB), small for gestational age (SGA) infants, and hypertensive disorders of pregnancy (HDP). Few studies with data from nationwide cohorts have elucidated the association between MA and obstetric complications comprehensively while accounting for the subdivided objective biomarkers of MA.What this Study Adds? MA with subdivided total serum IgE levels was associated with various obstetric complications. Total serum IgE level may be a potential prognostic marker for pregnant women with MA to predict the potential risk of PTB, SGA infants, and HDP.

Influence of preconception carbohydrate intake on hypertensive disorders of pregnancy: The Japan Environment and Children's Study.

AIM: Hypertensive disorders of pregnancy (HDP) are a crucial cause of morbidity and mortality. We aimed to examine whether preconception carbohydrate intake is associated with new-onset HDP and small for gestational age (SGA) births. METHODS: We identified 93 265 normotensive (primiparous, 37 387; multiparous, 55 878) participants from the Japan Environmental Children's Study database who delivered between 2011 and 2014. After excluding participants with multiple gestations, preconception hypertension, and insufficient data, primiparous and multiparous participants were categorized into five groups according to their preconception carbohydrate-intake quintiles (Q1 and Q5 were the lowest and highest groups, respectively). Multiple logistic regression analysis was performed to identify the effect of preconception carbohydrate intake on early (<34 weeks) and late-onset (≥34 weeks) HDP and the incidence of SGA births. RESULTS: With the middle carbohydrate intake group (Q3) as a reference, the risk for late-onset HDP among multiparous women was higher in the Q5 group (adjusted odds ratio [aOR] 1.31, 95% confidence interval [CI] 1.02-1.69). The incidence of SGA births was higher in the Q1 group among both primiparous (aOR 1.16, 95% CI 1.01-1.33) and multiparous women (aOR 1.16, 95% CI 1.02-1.32). CONCLUSIONS: Excessive carbohydrate intake increases the incidence of HDP in multiparous women, while low-carbohydrate intake increases the incidence of SGA births. New recommendations for preconception carbohydrate intake are required to prevent major HDP-related complications.

Tocolytic treatment and maternal characteristics, obstetric outcomes, and offspring childhood outcomes among births at and after 37 weeks of gestation: the Japan environment and children's study.

PURPOSE: To evaluate differences in maternal characteristics and obstetric and offspring childhood outcomes between births at and after 37 weeks of gestation (referred to as term and post-term births) according to the use of tocolytic treatment. METHODS: Data for 63,409 women with singleton births at and after 37 weeks of gestation were analyzed using data from the Japan Environment and Children's Study (JECS). We compared maternal characteristics, obstetric outcomes, and offspring childhood outcomes between term and post-term births exposed and not exposed to tocolytic treatment. Additionally, multivariable logistic regression models were used to calculate adjusted odds ratios for offspring childhood outcomes with significant between-group differences in the univariable analysis, with term and post-term births without tocolytic agents as the reference group. RESULTS: We observed differences in maternal characteristics and obstetric outcomes between term and post-term births exposed and not exposed to tocolytic treatment. The incidence of offspring childhood developmental disorders showed no significant between-group differences. However, participants exposed to tocolytic agents had higher incidence of offspring childhood allergic disorders. The adjusted odds ratio for any of the offspring childhood allergic disorders in term and post-term births with tocolytic agents was 1.08 (95% confidence interval, 1.03-1.13). CONCLUSION: This study found no significant difference in the incidence of offspring developmental disorders between term and post-term births exposed and not exposed to tocolytic treatment. However, tocolytic treatment was associated with differences in maternal characteristics and obstetric outcomes, along with a marginal increase in the incidence of childhood allergic disorders in offspring.

Maternal folic acid supplement use/dietary folate intake from preconception to early pregnancy and neurodevelopment in 2-year-old offspring: the Japan Environment and Children's Study.

We evaluated the association between maternal prenatal folic acid supplementation/dietary folate intake and motor and cognitive development in 2-year-old offspring using data from the Japan Environment and Children's Study database. Neurodevelopment of 2-year-old offspring were evaluated using the Kyoto Scale of Psychological Development 2001. In total, data of 3839 offspring were analysed. For folic acid supplementation, a multiple regression analysis showed that offspring of mothers who started using folic acid supplements before conception had a significantly lower developmental quotient (DQ) in the postural-motor DQ area than offspring of mothers who did not use them at any time throughout their pregnancy (partial regression coefficient (B) -2·596, 95 % CI -4·738, -0·455). Regarding daily dietary folate intake from preconception to early pregnancy, a multiple regression analysis showed that the group with ≥ 200 µg had a significantly higher DQ in the language-social area than the group with <200 µg. The DQ was higher in the ≥ 400 µg group (B 2·532, 95 % CI 0·201, 4·863) than the 200 to <400 µg group (B 1·437, 95 % CI 0·215, 2·660). In conclusion, our study showed that maternal adequate dietary folate intake from preconception to early pregnancy has a beneficial association with verbal cognition development in 2-year-old offspring. On the other hand, mothers who started using folic acid supplements before conception had an inverse association with motor development in 2-year-old offspring. There were no details on the amount of folic acid in the supplements used and frequency of use. Therefore, further studies are required.

Meconium-stained amniotic fluid during labor may be a protective factor for the offspring's childhood wheezing up to 3 years of age: the Japan Environment and Children's Study.

We aimed to evaluate the association between meconium-stained amniotic fluid during labor and offspring's childhood wheezing. This study analyzed the data of participants enrolled in the Japan Environment and Children's Study, a nationwide prospective birth cohort study, between 2011 and 2014. Data of women with singleton live births between 22 and 40 weeks' gestation were analyzed. Participants were categorized into two groups according to the presence or absence of meconium-stained amniotic fluid. The primary outcome measure was the offspring's childhood wheezing up to 3 years of age. A logistic regression model was used to calculate the adjusted odds ratio for childhood wheezing in children of women with meconium-stained amniotic fluid, considering those without meconium-stained amniotic fluid as a reference, taking into account the potential confounding factors affecting the incidence of wheezing. We analyzed data from 61,991 participants: 1796 (2.9%) participants had meconium-stained amniotic fluid during labor and 18,919 (30.5%) of the offspring had childhood wheezing. The adjusted odds ratios for the offspring's childhood wheezing were 0.89 (95% confidence interval, 0.79-0.99) in total participants, 0.87 (95% confidence interval, 0.78-0.97) in term births, and 2.00 (95% confidence interval, 0.98-4.09) in preterm births. CONCLUSIONS: This study revealed a decreased incidence of childhood wheezing among the children of women with meconium-stained amniotic fluid in term births. By yet unknown mechanisms, meconium-stained amniotic fluid was associated with a decreased incidence of childhood wheezing in the offspring. Further studies are required to clarify the mechanism of one's own meconium in affecting their health condition. WHAT IS KNOWN: • Meconium-stained amniotic fluid during labor is associated with several adverse perinatal outcomes, and meconium aspiration syndrome is associated with offspring's childhood asthma and wheezing. • Meconium-stained amniotic fluid during labor could be an independent protective factor for the offspring's dermatitis and skin rash. WHAT IS NEW: • Whole cases with meconium-stained amniotic fluid during labor were associated with a decreased incidence of offspring's childhood wheezing up to 3 years of age. • This study may shed light on the effects of simple meconium-stained amniotic fluid on offspring's childhood health.

Association of preconception dysmenorrhea with obstetric complications: the Japan Environment and Children's Study.

BACKGROUND: The association of maternal preconception dysmenorrhea, especially primary dysmenorrhea, with obstetric complications has not been clearly described. Therefore, we evaluated the association of preconception dysmenorrhea with obstetric complications while accounting for the presence of pelvic pathologies. METHODS: We analyzed the data of women with singleton live births at and after 22 weeks of gestation enrolled in the Japan Environment and Children's Study, a nationwide birth cohort study, between 2011 and 2014. Participants with psychological disorders were excluded. Preconception dysmenorrhea, identified in the medical record transcripts, was categorized into mild dysmenorrhea (MD) and severe dysmenorrhea (SD). Furthermore, excluding those who had pelvic pathologies via self-reported questionnaires (endometriosis, adenomyosis, and uterine myomas) with MD and SD, preconception dysmenorrhea was categorized into mild primary dysmenorrhea (MPD) and severe primary dysmenorrhea (SPD), respectively. Using multiple logistic regression, adjusted odds ratios (aORs) for obstetric complications, including preterm birth (PTB) before 37 weeks and 34 weeks, small-for-gestational-age infants, preterm premature rupture of membrane, and hypertensive disorders of pregnancy, were calculated (considering confounders) in women with (1) MD or SD and (2) MPD or SPD. Women without preconception dysmenorrhea were used as a reference. RESULTS: A total of 80,242 participants were analyzed. In women with SD, the aOR for PTB before 37 weeks was 1.38 (95% confidence interval [CI] 1.10, 1.72). In women with SPD, the aOR for PTB before 37 weeks was 1.32 (95% CI 1.02, 1.71). There was no association between women with MD or MPD and obstetric complications. CONCLUSIONS: SD and SPD are significantly associated with an increased incidence of PTB before 37 weeks. Care providers should provide proper counseling regarding the association between preconception dysmenorrhea and obstetric complications. Optimal management of pregnant women with preconception dysmenorrhea to reduce the incidence of PTB should be elucidated in further studies, with detailed clinical data of pelvic pathologies.

Age at menarche and risk of adverse obstetric outcomes during the first childbirth in Japan: The Japan Environment and Children's Study.

AIM: Age at menarche is used as a risk indicator of gestational diabetes mellitus, preterm birth, and fetal growth. However, little is known regarding the age impact on obstetric outcomes among nulliparous women. This study investigated whether menarche age was correlated with obstetric outcomes among nulliparous women. METHODS: We analyzed the data obtained for 37 645 singleton pregnancies between 2011 and 2014 in the Japan Environment and Children's Study. Age at menarche was categorized into the ≤9-, 10-, 11-, 12-, 13-, 14-, and ≥15-year-old groups (n = 363, 3155, 8390, 11 164, 6713, 5446, and 2414, respectively). We calculated the relative risk for cases of preterm birth <37 weeks, low birthweight <2500 g, small for gestational age, early and late-onset hypertension disorders of pregnancy, and early- and late-diagnosed (diagnosed < or ≧ 24 weeks) gestational diabetes mellitus using a reference of 12 years at menarche. RESULTS: Women with an age at menarche ≤9 years showed an increased incidence of developing early-diagnosed gestational diabetes mellitus (relative risk: 2.42; 95% confidence interval: 1.05-5.60). A high body mass index before pregnancy increased the risk of developing gestational diabetes mellitus. CONCLUSIONS: Age at menarche helped in assessing the risk of early-diagnosed gestational diabetes mellitus among nulliparous women. Future studies are needed to clarify the underlying mechanisms. This study is the first to use data from the largest prospective birth cohort study of Japan and to investigate the relationship between menarche age and obstetric outcomes among nulliparous women.

Association between maternal ritodrine hydrochloride administration during pregnancy and childhood wheezing up to three years of age: The Japan environment and children's study.

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 analyzed the data of the participants enrolled in the Japan Environment and Children's Study, a nationwide prospective birth cohort study, between 2011 and 2014. Data of women with singleton live births after 22 weeks of gestation were analyzed. The participants were divided according to MRA status. Considering childhood factors affecting the incidence of wheezing, including smoking environment and childhood viral infections, a logistic regression model was used to calculate 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. Additionally, participants were stratified by term births, and 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 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 a slightly increased incidence of childhood wheezing up to three years, irrespective of term or preterm birth status. It is important that perinatal physicians consider the potential effects of MRA on the offspring's childhood health.

Maternal sleep duration and neonatal birth weight: the Japan Environment and Children's Study.

BACKGROUND: The adequate maternal sleep duration required for favorable obstetric outcomes is unknown. We evaluated the association between maternal sleep duration and low birth weight infants, small for gestational age infants, and macrosomia. METHODS: Participants enrolled in the Japan Environment and Children's Study, a nationwide birth cohort study, with singleton pregnancies after 22 weeks, who gave birth between 2011 and 2014 were enrolled and categorized into five groups according to maternal sleep duration during pregnancy: < 6.0 h, 6.0-7.9 h, 8.0-8.9 h, 9.0-9.9 h, and 10.0-12.0 h. We evaluated the association between maternal sleep duration and the incidence of low birth weight infants (< 2500 g), very low birth weight infants (< 1500 g), small for gestational age infants, and macrosomia (> 4000 g), with women with maternal sleep duration of 6.0-7.9 h as the reference, using a multiple logistic regression model. RESULTS: In total, 82,171 participants were analyzed. The adjusted odds ratios (95% confidence intervals) for low birth weight infants in women with maternal sleep duration of 9.0-9.9 h and 10.0-12.0 h and for small for gestational age infants in women with maternal sleep duration of 9.0-9.9 h were 0.90 (0.83-0.99), 0.86 (0.76-0.99), and 0.91 (0.82-0.99), respectively, before adjusting for excessive gestational weight gain. No significant association was observed between maternal sleep duration and these outcomes after adjusting for excessive gestational weight gain. Among women with appropriate gestational weight gain, the adjusted odds ratios (95% confidence intervals) for low birth weight infants and for small for gestational age infants with sleep duration of 9.0-9.9 h were 0.88 (0.80-0.97) and 0.87 (0.78-0.97), respectively. CONCLUSIONS: Maternal sleep duration of 9.0-9.9 h was significantly associated with the decreased incidence of low birth weight infants and small for gestational age infants in pregnant women with appropriate gestational weight gain, compared with that of 6.0-7.9 h. Care providers should provide proper counseling regarding the association between maternal sleep duration and neonatal birth weight and suggest comprehensive maternal lifestyle modifications to prevent low birth weight and small for gestational age infants.

Nonreassuring fetal status during labor and offspring's childhood neurodevelopment at 3 years of age: The Japan Environment and Children's Study.

OBJECTIVE: Although prior attempts have failed to identify the beneficial effects of intensive fetal monitoring on cerebral palsy, the association between nonreassuring fetal status (NRFS) during labor and the incidence of long-term neurodevelopmental delays in offspring remains unclear. This study aimed to evaluate this association using a nationwide birth cohort. METHODS: Data from 72 869 women with singleton deliveries at and after 37 weeks of gestation from the Japan Environment and Children's Study (2011-2014) were analyzed. Multivariable logistic regression models were used to analyze the odds ratios (ORs) for neurodevelopmental delays using the Ages & Stages Questionnaire (Third Edition) in offspring aged 3 years. RESULTS: The adjusted ORs for personal-social problems were 1.52 (95% confidence interval [CI], 1.06-2.16) for offspring delivered vaginally by nulliparous mothers and 1.51 (95% CI, 1.05-2.18) (for males, 1.70 [95% CI, 1.15-2.50]) for those delivered via cesarean section. No significant changes in adjusted ORs for neurodevelopmental delays were observed among participants without neonatal Apgar scores (ASs) <7 and without umbilical arterial pH (UmA-pH) <7.20. CONCLUSION: NRFS during labor was associated with an increased incidence of personal-social problems in offspring aged 3 years. However, this association was not confirmed after excluding participants with neonatal ASs <7 and UmA-pH <7.20. The association between NRFS and offspring's neurodevelopmental delays might vary based on delivery settings, offspring sex, and short-term neonatal outcomes.

Association of Preconception or Antepartum Maternal Intimate Partner Violence with Autism Spectrum Disorder in 3-Year-Old Offspring: The Japan Environment and Children's Study.

Objective: We investigated the association between maternal antepartum intimate partner violence (IPV) and autism spectrum disorder (ASD) in 3-year-old offspring. Materials and Methods: Secondary analysis of the Japan Environment and Children's Study, a nationwide prospective birth-cohort study, for preconceptional and antepartum psychological/physical IPV against mothers was undertaken based on data obtained from a maternal self-report questionnaire. Subgroup analysis by four-level IPV frequency versus no IPV was conducted, and the incidence of ASD diagnosed during ages 2-3 years was estimated using self-reported questionnaire data of participants from when the child was 3 years old. Multivariate logistic regression was used to determine the association of preconceptional/antepartum IPV with ASD in 3-year-old offspring. Results: Among 79,324 offspring, 355 (0.45%) had ASD; preconceptionally and prenatally, 1,504 (1.9%) and 839 (1.1%) mothers were exposed to physical IPV whereas 9,162 (11.6%) and 10,240 (12.9%) mothers were exposed to psychological IPV, respectively. Multivariate logistic regression revealed a significant association of preconceptional physical IPV with ASD in offspring (adjusted odds ratio, 3.21; 95% confidence interval, 1.24-8.31), but not for antepartum physical IPV and preconceptional and antepartum psychological IPV. Conclusion: Preconceptional, but not antepartum, physical IPV was associated with ASD in 3-year-old offspring. Preconceptional and antepartum psychological IPV was unassociated with ASD in 3-year-old offspring. Preconceptional care through prevention of preconceptional physical IPV is important for neurodevelopment in offspring, and the mechanisms underlying the effects of IPV among nonpregnant individuals on ASD development in offspring should be elucidated.

Association between preconception dietary fiber intake and hypertensive disorders of pregnancy: The Japan Environment and Children's Study.

OBJECTIVES: Hypertensive disorders of pregnancy (HDP) are a significant cause of morbidity and mortality. This study aimed to investigate whether preconception dietary fiber intake is associated with new-onset HDP. STUDY DESIGN: We identified 84,873 (primipara, 33,712; multipara, 51,161) normotensive participants from the Japan Environmental Children's Study database who delivered between 2011 and 2014. The participants were subsequently categorized into five groups based on their preconception dietary fiber intake quintiles (Q1-Q5). MAIN OUTCOME MEASURES: The main obstetric outcome was HDP, and the secondary obstetric outcomes included early-onset (Eo, <34 weeks)-HDP, late-onset (Lo, ≥34 weeks)-HDP, small for gestational age (SGA) births, and HDP with/without SGA. RESULTS: Multiple logistic regression analysis showed that in primiparas, the risks of HDP, Lo-HDP, and HDP without SGA were lower in the Q5 group compared with the Q3 group (HDP: adjusted odds ratio [aOR] = 0.73, 95 % confidence intervals [95 % CI] = 0.58-0.93; Lo-HDP: aOR = 0.72, 95 % CI = 0.55-0.94; and HDP without SGA: aOR = 0.68, 95 % CI = 0.53-0.88). However, the risks of Eo-HDP and HDP with SGA were higher in the Q1 group compared with the Q3 group (Eo-HDP: aOR = 1.66, 95 % CI = 1.02-2.70; and HDP with SGA: aOR = 1.81, 95 % CI = 1.04-3.17). In multiparas, the risks of Lo-HDP and SGA were higher in the Q1 group compared with the Q3 group (Lo-HDP: aOR = 1.47, 95 % CI = 1.10-1.97; SGA: aOR = 1.17, 95 % CI = 1.02-1.35). CONCLUSIONS: Preconception dietary fiber intake is beneficial in preventing HDP onset. Therefore, new recommendations should be considered to encourage higher dietary fiber intake as part of preconception care.

Urinary 8-hydroxy-2'-deoxyguanosine levels and preterm births: a prospective cohort study from the Japan Environment and Children's Study.

OBJECTIVES: To evaluate the association between urinary 8-hydroxy-2'-deoxyguanosine (U8-OHdG) level-a marker of oxidative stress-and the incidence of preterm births (PTBs). DESIGN: Prospective cohort study. SETTING: The Japan Environment and Children's Study (JECS). PARTICIPANTS: Data from 92 715 women with singleton pregnancies at and after 22 weeks of gestation who were enrolled in the JECS, a nationwide birth cohort study, between 2011 and 2014 were analysed. U8-OHdG levels were assessed once in the second/third trimester using liquid chromatography-tandem mass spectrometry. Participants were categorised into the following three or five groups: low (<1.95 ng/mg urinary creatinine (Cre)), moderate (1.95-2.94 ng/mg Cre) and high (≥2.95 ng/mg Cre) U8-OHdG groups, or groups with <1.87, 1.87-2.20, 2.21-2.57, 2.58-3.11 and ≥3.12 ng/mg Cre. For stratification, participants with representative causes for artificial PTB were excluded. PRIMARY AND SECONDARY OUTCOME MEASURES: Adjusted OR (aOR) for PTB before 37 and 34 weeks of gestation were calculated using a multivariable logistic regression model while adjusting for confounding factors; the moderate or lowest U8-OHdG group was used as the reference, respectively. RESULTS: The aORs for PTB before 37 weeks of gestation in the high U8-OHdG group were 1.13 (95% CI 1.05 to 1.22) and 1.13 (95% CI 1.04 to 1.23) after stratification. The aOR for PTB before 37 weeks in the fourth group was 0.90 (95% CI 0.81 to 0.99). After stratification, the aORs for PTB before 37 and 34 weeks in the fifth group were 1.15 (95% CI 1.03 to 1.29) and 1.46 (95% CI 1.08 to 1.97), respectively. CONCLUSIONS: High U8-OHdG levels were associated with increased PTB incidence, especially in participants without representative causes for artificial PTB. Our results can help identify the mechanisms leading to PTB, considering the variable aetiologies of this condition; further validation is needed to clarify clinical impacts.

Association between daily breakfast habit during pregnancy and neurodevelopment in 3-year-old offspring: The Japan Environment and Children's Study.

The association between daily breakfast habits during pregnancy and offspring neurodevelopment remains unknown. We evaluated the association between breakfast habits during pregnancy and offspring neurodevelopment. Data of 72,260 women with singleton deliveries at and after 37 weeks of gestation enrolled during 2011-2014 in the Japan Environment and Children's Study were analysed. Offspring neurodevelopmental delays at 3 years of age were evaluated using the Ages and Stages Questionnaire, Third Edition (ASQ-3). Participants were stratified by tertiles of maternal daily energy intake (DEI) (Groups 1, 2, and 3:< 1400, 1400-1799, and ≥ 1800 kcal, respectively) during pregnancy and by offspring sex. The adjusted odds ratio (aOR) for abnormality in communication among participants with daily breakfast consumption habit was 0.87 (95% confidence interval, 0.80-0.96). A stratified analysis based on total DEI showed no significant differences in the neurodevelopment of Group 1 offspring. The aOR for abnormality in communication was 0.80 (95% confidence interval, 0.68-0.94) in Group 2. The aOR for abnormality in personal-social characteristics was 0.84 (95% confidence interval, 0.71-0.99) in Group 3. Maternal daily breakfast habits are associated with offspring neurodevelopment at 3 years of age, with the association influenced by maternal DEI and offspring sex.

Association of cesarean section and infectious outcomes among infants at 1 year of age: Logistic regression analysis using data of 104,065 records from the Japan Environment and Children's Study.

BACKGROUND: There has been a recent decrease in the prevalence of infectious diseases in children worldwide due to the usage of vaccines. However, the association between cesarean delivery and infectious diseases remains unclear. Here, we aimed to clarify the association between cesarean delivery and the development of infectious diseases. METHODS: This study is a cross-sectional study. We used data from the Japan Environment and Children's Study, which is a prospective, nationwide, government-funded birth cohort study. The data of 104,065 records were included. Information about the mode of delivery, central nervous system infection (CNSI), otitis media (OM), upper respiratory tract infection (URTI), lower respiratory tract infection (LRTI), gastrointestinal infection (GI), and urinary tract infection (UTI) was obtained from questionnaires and medical records transcripts. Multiple logistic regression analysis was used to assess the association between cesarean delivery and CNSI, OM, URTI, LRTI, GI, and UTI risk. RESULTS: We included a total of 74,477 subjects in this study, of which 18.4% underwent cesarean deliveries. After adjusting for the perinatal, socioeconomic, and postnatal confounding factors, children born by cesarean delivery did not have an increased risk of developing CNSI (95% confidence interval [CI] 0.46-1.35), OM (95% CI 0.99-1.12), URTI (95% CI 0.97-1.06), LRTI (95% CI 0.98-1.15), GI (95% CI 0.98-1.11), or UTI (95% CI 0.95-1.45). CONCLUSIONS: This nationwide cohort study did not find an association between cesarean delivery and CNSI, OM, URTI, LRTI, GI, and UTI. However, further studies are needed to evaluate the role of cesarean delivery in the development of infectious diseases.

Congenital Anomalies in Infants in Fukushima from 2011 to 2014: The Japan Environment and Children's Study.

Introduction: This study aimed to assess congenital anomalies among infants from 2011 to 2014 in Fukushima and compare the assessment with that from other geographical regions in Japan. Methods: We used the dataset of the Japan Environment and Children's Study (JECS), which is a nationwide prospective birth cohort study. For the JECS, participants were recruited through 15 regional centers (RC), including Fukushima. Pregnant women were recruited between January 2011 and March 2014. The Fukushima RC recruited all municipalities in the Fukushima Prefecture, from where we compared congenital anomalies in infants from the Fukushima RC to those in the infants from 14 other RCs. Crude and multivariate logistic regression analyses were also performed, with the multivariate logistic regression analysis being adjusted for maternal age, maternal body mass index (kg/m2), infertility treatment, multiple pregnancies, maternal smoking, maternal alcohol consumption, pregnancy complications, maternal infection, and infant sex. Results: In the Fukushima RC, 12,958 infants were analyzed, and 324 infants were diagnosed with major anomalies (2.50%). In the remaining 14 RCs, 88,771 infants were analyzed and 2,671 infants were diagnosed with major anomalies (3.01%). Crude logistic regression analysis demonstrated that the odds ratio for the Fukushima RC was 0.827 (95% confidence interval, 0.736-0.929) using the other 14 RCs as a reference. Multivariate logistic regression analysis also demonstrated that the adjusted odds ratio was 0.852 (95% confidence interval, 0.757-0.958). Conclusions: Fukushima Prefecture was found not to be an area at high risk for the occurrence of congenital anomalies in infants compared nationwide in Japan from 2011 to 2014.