Severity of low pre-pregnancy body mass index and perinatal outcomes: the Japan Environment and Children's Study

Gender differences in the proportion of Japanese parents meeting 24-h movement guidelines and associations with weight status

OBJECTIVES

Parents' healthy behaviors are important for both their health and role models for their children. The purpose of this study was to evaluate adherence to the three recommendations associated with health in the Canadian 24-h movement or Japanese physical activity (PA) guidelines and their relationship with weight status (underweight or obesity) in Japanese parents.

METHODS

This cross-sectional study included 425 mothers and 237 fathers. Meeting the 24-h movement guidelines was defined as: ≥150 min/week of moderate-to-vigorous PA (MVPA) (Canada) or at least 60 min/day of MVPA (Japan), ≤8 h/day of sedentary time which includes ≤3 h of recreational screen time, and 7 to 9 h/night of sleep. MVPA and sedentary time were accelerometer-determined while screen time and sleep duration were self-reported.

RESULTS

The prevalence of mothers meeting all three recommendations was 30.6% using Canadian PA guidelines and 20.7% using Japanese PA guidelines, while that of fathers was 10.6% and 8.0%, respectively. Mothers not meeting the sedentary behavior recommendation had a lower odds ratio and those not meeting Japanese PA recommendations had a higher odds ratio for underweight compared to mothers meeting the recommendations, adjusted for age and area socioeconomic status.

CONCLUSIONS

The screen time recommendation and Japanese PA recommendation were associated with underweight in mothers. None of the recommendations was associated with weight status in fathers. Further research is needed to understand the relationships among movement behaviors and weight status, particularly among Japanese women, whose routine behaviors, such as household activities, may be misclassified by a questionnaire.

Pre-pregnancy body mass index and low birthweight: Secondary data analysis using health insurance claims data in Japan

AIM

For women, being underweight increases their susceptibility to osteoporosis, anemia, and other conditions and affects the weight of their infants and the well-being of future generations. This study examined the association between low pre-pregnancy body mass index (BMI) and low birthweight using health insurance claims data and health checkup data, including weight measurements.

METHODS

We used health insurance claims data and health checkup data (JMDC, Tokyo, Japan) of women and their newborns in Japan between 2006 and 2020. We used checkup data, which included more accurate weight measurements and blood test-based diagnoses of anemia and hyperlipidemia compared to self-reported data. Maternal pre-pregnancy BMI was compared across three groups: underweight (BMI <18.5 kg/m2), normal weight (BMI 18.5-24.9 kg/m2), and overweight (BMI ≥25.0 kg/m2). The primary outcome was low birthweight (<2500 g), and secondary outcome was preterm childbirth. Logistic regression analyses were conducted to compare outcomes in the three groups by BMI. The underweight BMI group was considered as the reference group. A subgroup analysis was performed by maternal age.

RESULTS

In total, 16 363 mothers (underweight, 3418 [21%], normal weight, 11 493 [70%], and overweight, 1452 [8.9%]) were included. The risk of primary outcome (low birthweight) was significantly lower in the normal weight group than in the underweight group (4.6% vs. 5.7%; adjusted odds ratio 0.78 [95% confidence interval: 0.65-0.96]). In the subgroup analyses, no significant differences were noted in the incidences of low birthweight and preterm childbirth between maternal age groups.

CONCLUSIONS

Pre-pregnancy BMI was associated with an increased risk of delivering low-birthweight infant. Awareness about the importance of women's pre-pregnancy health and appropriate BMI may reduce the incidence of low birthweight.

Lower ERVW-1 and higher VEGF, FLT-1 and HIF-1 gene expression in placentae of low birth babies from Indonesia

INTRODUCTION

Poor placental angiogenesis is associated with several pregnancy complications including fetal growth restriction (FGR), which causes low birth weight (LBW) babies to have a high risk of growth disorders and metabolic disorders in adulthood. Recent research using syncytin knock-out mice showed significant disruption in the growth of placental vascularization. Syncytin-1 which encoded by ERVW-1 gene, is proposed to have a role in placental angiogenesis, but its relationship with other proangiogenic factors such as vascular endothelial growth factor (VEGF) in the placenta of LBW babies has not yet been determined. By knowing the mechanisms of FGR, more proactive preventive and therapeutic measures can be taken in the future. This study aimed to determine the expression of ERVW-1, proangiogenic gene VEGF and its receptor (FLT-1), and hypoxia inducible factor-1 (HIF-1) in LBW placentas, and investigate the relationship between these genes' expression in the placenta of LBW babies.

METHODS

Total RNA was extracted from placental tissue. Total RNA is used as a cDNA synthesis template, followed by qRT-PCR. Correlations of ERVW-1, VEGF, FLT-1 and HIF-1 genes' expression were analyzed by linear regression.

RESULTS

The age and body mass index of mothers with LBW and normal birth weight (NBW) babies were not significantly different. ERVW-1 expression in LBW placentas was lower than in NBW placentas, but VEGF, FLT-1 and HIF-1 expressions were higher. ERVW-1 was negatively correlated with HIF-1 and VEGF.

DISCUSSION

Low expression of ERVW-1 in the placenta of LBW babies may result in impaired placental angiogenesis and possibly lead to hypoxia.

Maternal excessive weight gain as a potential risk factor for prolonged labor in Japanese pregnant women: The Japan Environment and Children's Study

AIM

This study aimed to determine whether excessive maternal weight gain during pregnancy was associated with a higher risk of prolonged labor.

METHODS

We analyzed the data regarding maternal weight gain during pregnancy for the participants of Japan Environment and Children's Study (JECS), which is an ongoing nationwide prospective birth cohort study in Japan. After excluding participants with multiple pregnancies, with deliveries before 37 or beyond 42 weeks of gestation, or who had undergone cesarean section, 71,154 (nulliparous, n = 28,442) Japanese women were included. Prolonged labor was defined by a cutoff ranking at the 95th percentile and consequently defined as labor duration exceeding 12.7 h in multiparous women and exceeding 23.2 h in nulliparous women. These classifications were made according to labor curves established by the Japanese Society of Obstetrics and Gynecology Perinatal Committee developed in June 2021. Considering that no studies have conducted an investigation based on this new guideline, we analyzed the association between excessive maternal weight gain during pregnancy and prolonged labor by parity.

RESULTS

The overall incidence of prolonged labor was 10.2% (2,907/28,442) in nulliparous women and 6.1% (2,597/42,712) in multiparous women. Multivariable analysis indicated that excessive maternal weight gain was significantly associated with prolonged labor in nulliparous (adjusted odds ratio, 1.21; 95% confidence interval, 1.10-1.32) and multiparous women (adjusted odds ratio, 1.15; 95% confidence interval, 1.05-1.27). Kaplan-Meier survival analysis showed that as labor progressed, the percentage of women who had not yet delivered was higher among those with excessive maternal weight gain than among those with normal maternal weight gain in both the nulliparous (median labor duration 12.9 h vs 12.2 h, p<0.001) and multiparous (median labor duration 6.2 h vs 5.8 h, p<0.001) groups.

CONCLUSION

Excessive maternal weight gain was significantly associated with prolonged labor in Japanese women.

Association between Perinatal Outcomes and Maternal Risk Factors: A Cohort Study

Background and Objectives: The aim of this study was to analyze the association between maternal risk factors, such as age, body mass index (BMI), and cigarette smoking, and perinatal outcomes. Materials and Methods: We conducted a retrospective analysis based on prospectively collected data at Hospital Universitario de Torrejón (Madrid, Spain) between September 2017 and December 2019. All pregnant women with singleton pregnancies and non-malformed live fetuses attending their routine ultrasound examination at 11+0 to 13+6 weeks' gestation were invited to participate. The association between preeclampsia, preterm birth, gestational diabetes mellitus (GDM), small-for-gestational-age (SGA) or fetal-growth-restricted (FGR) neonates, and type of delivery and maternal age, BMI, and cigarette smoking was studied. Logistic mixed models were used to analyze the data. Results: A total of 1921 patients were included in the analysis. Women who were ≥40 years old had a significantly higher risk of having GDM (odds ratio (OR) 1.61, 95% confidence interval (CI) 1.08 to 2.36) and SGA neonates (OR 1.54, 95% CI 1.00 to 2.37). Women with a BMI < 18 had an increased rate of giving birth to SGA and FGR neonates (OR 3.28, 95% CI 1.51 to 7.05, and OR 3.73, 95% CI 1.54 to 8.37, respectively), whereas women with a BMI ≥ 35 had a higher risk of GDM (OR 3.10, 95% CI 1.95 to 4.89). Smoking increased the risk of having SGA and FGR neonates (OR 1.83, 95% CI 1.36 to 2.46, and OR 1.91, 95% CI 1.29 to 2.78). Conclusions: Advanced maternal age, low or high BMI, and smoking status are significant risk factors for pregnancy complications. Both clinicians and society should concentrate their efforts on addressing these factors to enhance reproductive health.

Maternal pre-pregnancy body mass index and related factors: A cross-sectional analysis from the Japan Environment and Children's Study

Socioeconomic status and smoking are reportedly associated with underweight and obesity; however, their associations among pregnant women are unknown. This study aimed to investigate whether socioeconomic factors, namely educational attainment, household income, marital status, and employment status, were associated with pre-pregnancy body mass index (BMI) categories, including severe-moderate underweight (BMI ≤ 16.9 kg/m2), mild underweight (BMI, 17.0-18.4 kg/m2), overweight (BMI, 25.0-29.9 kg/m2), and obese (BMI ≥ 30.0 kg/m2) among Japanese pregnant women using data from the Japan Environment and Children's Study (JECS). In total, pregnant women were included 96,751. Age- and parity-adjusted multivariable multinomial logistic regression analyses assessed socioeconomic factors and smoking associations with falling within abnormal BMI categories (normal BMI as the reference group). Lower education and lower household were associated with overweight and obesity, and, especially, lowest education and household income had relatively higher point estimate relative ratios (RRs) of 3.97 and 2.84, respectively. Regarding the risks for underweight, however, only junior high school education had a significantly higher RR for severely to moderately underweight. Regarding occupational status, homemakers or the unemployed had a higher RR for severe-moderate underweight, overweight, and obesity. Unmarried, divorced, or bereaved women had significantly higher RRs for mildly underweight status. Quitting smoking early in pregnancy/still smoking had higher RRs for all four not having normal BMI outcomes; however, quitting smoking before pregnancy had a higher RR only for obese individuals. Lower educational attainment and smoking are essential intervention targets for obesity and severe-moderate underweight prevention in younger women. Lower household income is also a necessary target for obesity.

Effects of the COVID-19 pandemic on the rates of adverse birth outcomes and fetal mortality in Japan: an analysis of national data from 2010 to 2022

BACKGROUND

Although the coronavirus disease 2019 (COVID-19) pandemic affected trends of multiple health outcomes in Japan, there is a paucity of studies investigating the effect of the pandemic on adverse birth outcomes and fetal mortality. This study aimed to investigate the effect of the onset of the pandemic on the trends in adverse birth outcomes and fetal mortality using national data in Japan.

METHODS

We used the 2010-2022 birth and fetal mortality data from the Vital Statistics in Japan. We defined the starting time of the effect of the pandemic as April 2020, and the period from January 2010 to March 2020 and that from April 2020 to December 2022 were defined as the pre- and post- pandemic period, respectively. The rates of preterm birth, term low birth weight (TLBW), small-for-gestational-age (SGA), large-for-gestational-age (LGA), spontaneous fetal mortality, and artificial fetal mortality were used as outcomes. An interrupted time series analysis was conducted using monthly time series data of the outcomes to evaluate the effects of the pandemic. In addition, a modified Poisson regression model was used to evaluate the effects of the pandemic on these outcomes using individual-level data, and the adjusted risk ratio of the effect was calculated.

RESULTS

The adverse birth and fetal mortality outcomes showed a decreasing trend over the years, except for preterm birth and LGA birth rates, and SGA birth rates tended to reach their lowest values after the onset of the pandemic. The interrupted time series analysis revealed that the pandemic decreased preterm birth, TLBW, and SGA birth rates. In addition, the regression analysis revealed that the pandemic decreased the TLBW, SGA, and artificial fetal mortality rates.

CONCLUSIONS

Analyses performed using national data suggested that the pandemic decreased the TLBW and SGA rates in Japan.

Maternal birth weight is an indicator of preterm delivery: the Japan environment and children's study

This study aimed to investigate the association between maternal birth weight (MBW) with preterm delivery (PTD) in the Japanese population. To this end, a total of 78,972 Japanese pregnant women were included in a prospective birth cohort study. Multiple logistic regression and multinominal logistic regression models were applied to investigate the associations of MBW with PTD (delivery from 22 to < 37 weeks of gestation), early PTD (delivery from 22 to < 34 weeks), and late PTD (delivery from 34 to < 37 weeks). The results showed that MBW was inversely associated with PTD, early PTD, and late PTD (p-for-trend < 0.0001, 0.0014, and < 0.0001, respectively). The adjusted odds ratios per each 500 g of MBW decrease were 1.167 (95% confidence interval [CI]: 1.118-1.218) for PTD, 1.174 (95% CI: 1.070-1.287) for early PTD and 1.151 (95% CI: 1.098-1.206) for late PTD. The effect size of the association of MBW with early PTD was similar to that with late PTD. This study demonstrated for the first time an association of a low MBW with PTD, early PTD, and late PTD in a Japanese nationwide cohort.

Underweight in young Japanese women over time: a longitudinal retrospective study of the change in body mass index from ages 6 to 20 years

BACKGROUND

The high prevalence of underweight in young women has become a serious health problem in Japan. When and how young women reach a low body mass index (BMI) has not been clarified.

AIM

To clarify the characteristics of BMI standard deviation scores (BMI SDS) trajectory of young Japanese women with underweight.

SUBJECTS AND METHODS

A total of 601 Japanese female university students aged 20 years were classified into underweight and healthy weight groups. Their school health check-up data were available from the ages of 6 to 20 years. We evaluated the estimated mean values of BMI SDS at each age and differences in BMI SDS (ΔBMI SDS) from 6 years to each age using a mixed-effects model and compared between the two groups at each age.

RESULTS

In the underweight group, the BMI SDS at every age (-1.67 to -0.91) and the ΔBMI SDS after 16 years of age (-0.76 to -0.38) were significantly lower than those in the healthy weight group (-0.41 to -0.13, -0.07 to 0.04), respectively.

CONCLUSION

Young Japanese women with underweight have at least two characteristics of BMI SDS trajectory: being constitutionally underweight and shifting their weight status from baseline towards underweight in their late teens.

Associated factors of undernutrition in children with congenital heart disease: a cross-sectional study

Objective

To evaluate the prevalence and associated factors of undernutrition among children with congenital heart disease (CHD) who have not undergone surgeries in China.

Methods

This cross-sectional study included 734 CHD children along with their parents. The outcome of interest was undernutrition, including underweight, wasting, and stunting, defined as Z-scores (i.e., weight-for-age, weight-for-height, and height-for-age) ≤-2, according to the World Health Organization (WHO) growth standard. Exposures of interest, containing demographics, obstetric factors, maternal dietary factors, parents' life behaviors and habits, birth-related factors, cardiac-related factors, and preoperative factors, were analyzed using a multivariate logistic regression model to test their associations with undernutrition in CHD children.

Results

Overall, 36.1%, 29.7%, and 21.3% of cases were underweight, wasted, and stunted, respectively. Multivariate logistic regression indicated that underweight was associated with demographic factors (including parents' occupational status, family income, and maternal body mass index pre-pregnancy), low birth weight (OR = 4.60, 2.76-7.70), pulmonary hypertension (OR = 4.46, 3.09-6.43), and pneumonia (OR = 1.88, 1.28-2.76). Artificially-fed children were 2.34 (1.36-4.01) times more likely to be underweight. Occupied mothers (OR = 0.62, 0.44-0.88) and fathers (OR = 0.49, 0.26-0.92) served as protective factors, while mothers having gestational complications (OR = 1.56, 1.11-2.18) and exposed to noisy environment (OR = 1.64, 1.11-2.42) during this pregnancy, and pulmonary hypertension (OR = 3.21, 2.30-4.49) increased the chance of wasting in offspring. The odds of being stunted were greater in families with >2 children (OR = 1.88, 1.13-3.14), placental abruption during this pregnancy (OR = 25.15, 2.55-247.89), preterm births (OR = 1.84, 1.02-3.31), low birth weight (OR = 3.78, 2.16-6.62), pulmonary hypertension (OR = 2.35, 1.56-3.53) and pneumonia (OR = 1.93, 1.28-2.90). In subgroup analyses, the associations differed between patients with different feeding patterns (breastfeeding vs. non-breastfeeding), CHD classifications (cyanotic vs. acyanotic), and prematurity (preterm vs. non-preterm).

Conclusion

Undernutrition is common in preoperative CHD children. Familial demographics, maternal factors (including having gestational complications and exposure to noisy environment during pregnancy), and patient-related factors (encompassing preterm births, low birth weight, pulmonary hypertension, pneumonia, and feeding pattern) were found to contribute to undernutrition in CHD cases. However, associated factors among the three subgroups of distinct feeding patterns, CHD categorization, and prematurity exhibited varied outcomes, suggesting the necessity for targeted interventions.

Interpregnancy weight change as a potential risk factor for large-for-gestational-age infants: the Japan Environment and Children's Study

OBJECTIVE

This study aimed to estimate the impact of interpregnancy weight change from the first to the second pregnancy on the risk of infants being large for gestational age (LGA).

METHODS

This nationwide prospective birth cohort analysis included 3245 women who delivered their first two live singletons between 2011 and 2014. Interpregnancy weight change was calculated as the difference between the prepregnancy body mass index (BMI) of the first and second pregnancies. LGA infants were compared among three interpregnancy weight change groups: weight loss (a BMI loss >1 unit), weight gain (a BMI gain >1 unit), and stable weight (BMI maintained within - 1 to <1 unit). Interpregnancy weight change was assessed in mothers with a BMI <25 and ≥25 kg/m², and adjusted odds ratios (ORs) were calculated for LGA infants by multiple logistic regression.

RESULTS

The incidence of LGA infants was 8.6% (279 out of 3245). Compared with the stable weight group, interpregnancy weight gain was associated with an increased risk of infants being LGA (adjusted OR: 1.69, 95% confidence interval: 1.21-2.36) in the normal BMI (<25 kg/m²) group. In contrast, in the overweight/obese BMI (≥25 kg/m²) group, interpregnancy BMI was not a significant risk factor for LGA infants.

CONCLUSIONS

Accurate risk stratification using interpregnancy BMI could assist the clinical management of women with a normal BMI who are at risk of delivering LGA infants.

Determinants of low birth weight among newborns delivered in China: a prospective nested case-control study in a mother and infant cohort

This nested case-control study aimed to investigate the determinants of low birth weight among newborn babies delivered in Shenzhen, Guangdong, China. We recorded socio-demographic data, health status before pregnancy, pregnancy outcomes and complications in a Shenzhen mother and infant cohort. Among 8951 cases, 401 (4.48%) had low birth weight and 1.65% were full-term with LBW. Maternal body mass index, family income, history of pregnancy, hypertension before pregnancy, vaginal bleeding in 1^st trimester, pregnancy-related diabetes, hypertension, placenta previa, placental abruption, premature rupture of membrane, oligohydramnios, and placental types were significantly associated with low birth weight (P < 0.05). In this study, high-risk and mainly preventable factors were linked to low birth weight. Adequate antenatal care, proper maternal nutrition and implementation of proven strategies to prevent high-risk factors may be effective ways to reduce the incidence of low birth weight.

Before Is Better: Innovative Multidisciplinary Preconception Care in Different Clinical Contexts

CONTEXT

Implementation of pre-conception care units is still very limited in Italy. Nowadays, the population's awareness of the reproductive risks that can be reduced or prevented is very low. Purpose and main findings: We presented a new personalized multidisciplinary model of preconception care aimed at identifying and possibly reducing adverse reproductive events. We analyzed three cohorts of population: couples from the general population, infertile or subfertile couples, and couples with a previous history of adverse reproductive events. The proposal involves a deep investigation regarding family history, the personal histories of both partners, and reproductive history.

PRINCIPAL CONCLUSIONS

Preconception care is still neglected in Italy and under-evaluated by clinicians involved in natural or in vitro reproduction. Adequate preconception counseling will improve maternal and fetal obstetrical outcomes.

Obesity as a potential risk factor for stillbirth: The Japan Environment and Children's Study

The relationship between high body mass index (BMI) >25 kg/m2 and risk for stillbirth in the Japanese population remains unclear. This study aimed to estimate the impact of maternal obesity on the risk of stillbirth in a Japanese population. This prospective cohort study used data from the Japan Environment and Children's Study, which recruited pregnant individuals between 2011 and 2014. A total of 93,772 fetuses were considered eligible for inclusion in this study. Stillbirth (fetal death before or during labor at ≥22 completed weeks of gestation) rates were compared among four pre-pregnancy BMI groups: underweight (<18.5 kg/m2), reference (18.5 to <25.0 kg/m2), overweight (25.0 to <30.0 kg/m2), and obese (≥30.0 kg/m2). The association between pre-pregnancy BMI and the risk of stillbirth was estimated using multiple logistic regression analyses. The overall stillbirth incidence was 0.33% (305/93,722). Compared with the reference group, the risk of stillbirth was significantly higher in the overweight group (adjusted odds ratio [aOR]: 1.55; 95% confidence interval [CI]: 1.08-2.23) and the obese group (aOR: 2.60; 95% CI: 1.59-4.24). The overall incidence of early stillbirth (i.e., <28 weeks) was 0.17% (155/93,722). Similarly, after adjusting for potential confounding factors, the risk of early stillbirth was significantly higher in the obese group (aOR: 4.33; 95% CI: 2.44-7.70). Increased maternal BMI was associated with an increased risk of stillbirth in the Japanese population. Therefore, counselling women planning for pregnancy on the importance of an appropriate pre-pregnancy BMI to minimize the risk of stillbirth is important.

Extreme temperature exposure increases the risk of preterm birth in women with abnormal pre-pregnancy body mass index: a cohort study in a southern province of China

Background

Prior literature has found that extreme temperature exposure is associated with preterm birth (PTB). However, current evidence provides heterogeneous conclusions, and data on extreme cold and across different pre-pregnancy body mass index (BMI) statuses are limited.

Methods

We conducted a population-based retrospective cohort of 251,257 women between 2014 and 2017 in Guangdong, China, to evaluate whether the association between extreme temperature exposure and PTB varied in pre-pregnancy BMI status. Participants were divided into three categories based on pre-pregnancy BMI: underweight (BMI < 18.5 kg/m2), normal weight (18.5-23.9 kg/m2), overweight or obesity (≥ 24.0 kg/m2). We fitted Cox proportional hazards models to assess the association between daily mean temperature and PTB at each trimester for each BMI category separately. The hazard ratios (HRs) at the 5th and 95th percentiles of temperature (defined as low and high temperatures respectively) were provided using the median temperature at each trimester as a reference.

Results

58,220 (23.2%) were underweight, and 27,865 (11.1%) were overweight or obese. Of the 251,257 women, 18,612 (7.41%) had PTB delivery. Both low-and high-temperature exposure increased the risk of PTB in the third trimester, while cold exposure mostly mitigated the risk for the first and second trimesters. The association with low temperature was the strongest in the third trimester, especially for underweight women (HR: 1.825; 95%CI: 1.529 ~ 2.179), while the association with high temperature was the strongest also in the third trimester, especially for obese or overweight women (HR:1.825; 95%CI:1.502 ~ 2.218). Furthermore, the attributable fractions of PTB risk in the third trimester were estimated as 5.59% (95% CI: 3.58, 7.98%) for cold exposure among underweight women and 3.31% (95% CI: 2.01, 4.88%) for hot exposure among overweight or obese women.

Conclusion

Exposure to either low temperature in the third trimester or high temperature during pregnancy was associated with a higher risk of PTB. Moreover, pre-pregnancy BMI status might affect the susceptibility of pregnant women. Such findings would be useful to develop targeted measures for vulnerable populations.

Diet Quality and Its Relationship with Weight Characteristics in Pregnant Japanese Women: A Single-Center Birth Cohort Study

Maternal underweight and inadequate gestational weight gain (GWG) are problems in Japan. However, increases in food intake aimed at weight gain alone are not sufficient for mother-child health. This study assessed diet quality based on the 3-day dietary records of pregnant women in an urban area of Japan in order to show the importance of evaluating diet quality, using the Nutrient-Rich Food Index 9.3 (NRF9.3), which is one metric based on nutrition profiling, and the Japanese Food Guide Spinning Top (JFGST). After excluding misreporters of energy intake, we stratified women (n = 91) by pre-pregnancy body mass index (BMI) and determined energy intake, diet quality status, and their relationship with GWG. Intakes of carbohydrate-containing staple foods, vegetable dishes, and fruit were insufficient regardless of BMI. Most of the underweight women with inadequate GWG had insufficient energy intake but high diet quality, as assessed by NRF9.3. In contrast, most women who consumed energy within the recommended range had low diet quality and gained weight at inappropriate levels. These results highlight the importance for pregnant Japanese women to maintain diet quality through a nutrient-dense diet, while simultaneously increasing energy intake after evaluation of their individual diet quality.

Parental pre-pregnancy body mass index and risk of low birth weight in offspring: A prospective cohort study in central China

Background

Low birth weight (LBW) is one of the most common adverse pregnancy outcomes. Previous studies have consistently shown that maternal body mass index (BMI) status before and during pregnancy is associated with LBW. However, previous studies lacked an association between paternal BMI and the conjunction effect of a couple's BMI and LBW in the offspring. Therefore, we established a cohort of pre-pregnancy couples to prospectively assess the relationship between maternal and paternal pre-pregnancy BMI and offspring LBW, very low birth weight (VLBW), and extremely low birth weight (ELBW).

Methods

A prospective cohort study was established in Central China. A total of 34,104 pregnant women with singleton pregnancies at 8-14 gestational weeks and their husbands were finally enrolled and followed to 3 months postpartum. The multivariate logistic regression and restrictive cubic spline model were used to explore the relationship between parental pre-pregnancy BMI and the risk of LBW, VLBW, and ELBW in offspring.

Results

Of the 34,104 participants, maternal pre-pregnancy overweight and obesity were associated with a higher risk of LBW (overweight: OR = 1.720, 95% CI = 1.533 ~ 1.930; obesity: OR = 1.710, 95% CI = 1.360 ~ 2.151), VLBW (overweight: OR = 2.283, 95% CI = 1.839 ~ 2.834; obesity: OR = 4.023, 95% CI = 2.855 ~ 5.670), and ELBW (overweight: OR = 3.292, 95% CI = 2.151 ~ 5.036; obesity: OR = 3.467, 95% CI = 1.481 ~ 8.115), while underweight was associated with a higher risk of LBW (OR = 1.438, 95% CI = 1.294 ~ 1.599) and a lower risk of ELBW (OR = 0.473, 95% CI = 0.236 ~ 0.946). Paternal pre-pregnancy overweight and obesity were associated with a higher risk of LBW (overweight: OR = 1.637, 95% CI = 1.501 ~ 1.784; obesity: OR = 1.454, 95% CI = 1.289 ~ 1.641) and VLBW (overweight: OR = 1.310, 95% CI = 1.097 ~ 1.564; obesity: OR = 1.320, 95% CI = 1.037 ~ 1.681), while underweight was associated with a lower risk of LBW (OR = 0.660, 95% CI = 0.519 ~ 0.839). Parents who were both excessive-weights in pre-pregnancy BMI, as well as overweight mothers and normal-weight fathers before pre-pregnancy, were more likely to have offspring with LBW, VLBW, and ELBW. Dose-response relationship existed between parental pre-pregnancy and LBW, VLBW, and ELBW, except for paternal BMI and ELBW.

Conclusions

Parental pre-pregnancy BMI was associated with the risk of LBW in offspring. Management of weight before pregnancy for couples might help reduce their adverse pregnancy outcomes in future intervention studies.

Correlation of body composition in early pregnancy on gestational diabetes mellitus under different body weights before pregnancy

OBJECTIVE

The prediction of gestational diabetes mellitus (GDM) by body composition-related indicators in the first trimester was analyzed under different body mass index (BMI) values before pregnancy.

METHODS

This was a retrospective analysis of pregnant women who were treated, had documented data, and received regular perinatal care at the Third Affiliated Hospital of Zhengzhou University from January 1, 2021, to December 31, 2021. Women with singleton pregnancies who did not have diabetes before pregnancy were included. In the first trimester (before the 14th week of pregnancy), bioelectric impedance assessment (BIA) was used to analyze body composition-related indicators such as protein levels, mineral levels, fat volume, and the waist-hip fat ratio. The Pearman's correlation coefficient was used to evaluate the linear relationship between the continuous variables and pre-pregnancy body mass index (BMI). In the univariate body composition analysis, the association with the risk of developing GDM was included in a multivariate analysis using the relative risk and 95% confidence interval obtained from logarithmic binomial regression, and generalized linear regression was used for multivariate regression analysis. Furthermore, the area under the curve (AUC) was calculated by receiver operating characteristic (ROC) curves. The optimal cutoff value of each risk factor was calculated according to the Youden Index.

RESULTS

In a retrospective study consisting of 6698 pregnant women, we collected 1109 cases of gestational diabetes. Total body water (TBW), protein levels, mineral levels, bone mineral content (BMC), body fat mass (BFM), soft lean mass (SLM), fat-free mass (FMM), skeletal muscle mass (SMM), percent body fat (PBF), the waist-hip ratio (WHR), the visceral fat level (VFL), and the basal metabolic rate (BMR) were significantly higher in the GDM group than in the normal group (P<0.05). Under the pre-pregnancy BMI groupings, out of 4157 pregnant women with a BMI <24 kg/m², 456 (10.97%) were diagnosed with GDM, and out of 2541 pregnant women with a BMI ≥24 kg/m², 653 (25.70%) were diagnosed with GDM. In the generalized linear regression model, it was found that in all groups of pregnant women, pre-pregnancy BMI, age, gestational weight gain (GWG) in the first trimester, and weight at the time of the BIA had a certain risk for the onset of GDM. In Model 1, without adjusting for confounders, the body composition indicators were all positively correlated with the risk of GDM. In Model 3, total body water, protein levels, mineral levels, bone mineral content, soft lean mass, fat-free mass, skeletal muscle mass, and the basal metabolic rate were protective factors for GDM. After Model 4 was adjusted for confounders, only the waist-hip ratio was positively associated with GDM onset. Among pregnant women with a pre-pregnancy BMI <24 kg/m², the body composition-related indicators in Model 2 were all related to the onset of GDM. In Model 3, total body water, soft lean mass, fat-free mass, and the basal metabolic rate were negatively correlated with GDM onset. In the body composition analysis of among women with a pre-pregnancy BMI ≥ 24 kg/m², only Model 1 and Model 2 were found to show positive associations with GDM onset. In the prediction model, in the basic data of pregnant women, the area under the receiver operating characteristic curve predicted by gestational weight gain for GDM was the largest (0.795), and its cutoff value was 1.415 kg. In the body composition results, the area under the receiver operating characteristic curve of body fat mass for predicting GDM risk was larger (0.663) in all pregnant women.

CONCLUSIONS

Through this retrospective study, it was found that the body composition-related indicators were independently associated with the onset of GDM in both the pre-pregnancy BMI <24 kg/m² and pre-pregnancy BMI ≥24 kg/m² groups. Body fat mass, the visceral fat level, and the waist-hip ratio had a higher correlation with pre-pregnancy BMI. Total body water, protein levels, mineral levels, bone mineral content, soft lean mass, fat-free mass, skeletal muscle mass, and the basal metabolic rate were protective factors for GDM after adjusting for some confounders. In all pregnant women, the waist-hip ratio was found to be up to 4.562 times the risk of GDM development, and gestational weight gain had the best predictive power for GDM. Gestational weight gain in early pregnancy, body fat mass, and the waist-hip ratio can assess the risk of GDM in pregnant women, which can allow clinicians to predict the occurrence of GDM in pregnant women as early as possible and implement interventions to reduce adverse perinatal outcomes.