Association of maternal birth weight with the risk of low birth weight and small-for-gestational-age in offspring: A prospective single-center cohort study

Should the Definition of Low Birth Weight Be Same in Every Ethnicity Considering the DOHaD Concept?

Low birth weight (LBW) is a significant concern not only because of its association with perinatal outcomes, but also because of its long-term impact on future health. Despite the physical differences among individuals of different ethnicities, the definition of LBW remains the same for all ethnicities. This study aimed to explore and discuss this issue. We compiled national data from several countries and found that maternal height was negatively correlated with LBW incidence. We discovered the INTERGROWTH-21st chart may not be suitable for the Japanese population, as the Japanese birth weight chart differs from the INTERGROWTH-21st chart. Researchers have reported different LBW cutoff values used to assess adverse perinatal outcomes for different countries. However, there is currently no definition of LBW independent of the mother's country of origin that can be used for predicting the risk of adverse health outcomes. Therefore, the current era of personalized healthcare may be the perfect time to establish a standard definition of LBW which is independent of the mother's country of origin. Considering the future of healthcare, it seems an apt time to discuss the development of a more meaningful definition of LBW that can be applied across ethnicities. Further research is needed to investigate the cutoff values of LBW in every ethnicity.

Diagnosis, Prevention, and Management of Fetal Growth Restriction (FGR)

Fetal growth restriction (FGR), or intrauterine growth restriction (IUGR), is still the second most common cause of perinatal mortality. The factors that contribute to fetal growth restriction can be categorized into three distinct groups: placental, fetal, and maternal. The prenatal application of various diagnostic methods can, in many cases, detect the deterioration of the fetal condition in time because the nature of the above disorder is thoroughly investigated by applying a combination of biophysical and biochemical methods, which determine the state of the embryo-placenta unit and assess the possible increased risk of perinatal failure outcome and potential for many later health problems. When considering the potential for therapeutic intervention, the key question is whether it can be utilized during pregnancy. Currently, there are no known treatment interventions that effectively enhance placental function and promote fetal weight development. Nevertheless, in cases with fetuses diagnosed with fetal growth restriction, immediate termination of pregnancy may have advantages not only in terms of minimizing perinatal mortality but primarily in terms of reducing long-term morbidity during childhood and maturity.

Maternal birth weight as an indicator of early and late gestational diabetes mellitus: The Japan Environment and Children's Study

AIMS

This study aimed to investigate the association of maternal birth weight (MBW) with early and late gestational diabetes mellitus (GDM).

METHODS

A total of 69318 pregnant Japanese women were included in this birth cohort study. The associations between maternal birth weight and early gestational diabetes mellitus (diagnosed at <24 gestational weeks) and late GDM (diagnosed at ≥24 gestational weeks) were investigated using a multinomial logistic regression model, with an maternal birth weight of 3000-3499 g as the reference category.

RESULTS

Lower maternal birth weight was associated with higher odds of developing early and late gestational diabetes mellitus (P < 0.0001 and P < 0.0001, respectively). The adjusted odds ratios (aORs) for early gestational diabetes mellitus in participants with a MBW of <2500 g and 2500-2999 g were 1.345 (95% confidence interval [CI]: 0.912-1.984) and 1.338 (95% CI: 1.098-1.629), respectively. The aORs for late gestational diabetes mellitus in participants with a MBW of <2500 g and 2500-2999 g were, 1.657 (95% CI: 1.298-2.115) and 1.218 (95% CI: 1.058-1.402), respectively.

CONCLUSIONS

Regardless of the gestational age when gestational diabetes mellitus was diagnosed, a lower maternal birth weight was associated with an increased risk of gestational diabetes mellitus. Furthermore, the association of a MBW <2500 g with late gestational diabetes mellitus tended to be stronger than that with early gestational diabetes mellitus.

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.

Association between Maternal Birth Weight and Prevalence of Congenital Malformations in Offspring: The Japanese Environment and Children's Study

Congenital malformations are functional and structural alterations in embryonic or foetal development resulting from a variety of factors including maternal health status. This study aimed to investigate the association between maternal birth weight (MBW) and the prevalence of congenital malformations in offspring using data from a nationwide birth cohort study in Japan including 103,060 pregnancies. A binary logistic regression model with adjustment for various covariates revealed that an MBW of <2500 g (low MBW) was associated with an increased risk of congenital heart disease (adjusted odds ratio: 1.388, [95% confidence interval: 1.075-1.792]), angioma (1.491 [1.079-2.059]), and inguinal hernia (1.746, [1.189-2.565]), while those with an MBW of ≥4000 g (high MBW) were associated with congenital anomalies of the urinary tract (2.194, [1.261-3.819]) and arrhythmia (1.775, [1.157-2.725]) compared with those with an MBW of 3000-3499 g. Low MBW was associated with cleft lip and/or palate (1.473, [1.052-2.064]), congenital heart disease (1.615, [1.119-2.332]), genital organs (1.648, [1.130-2.405]), hypospadias (1.804, [1.130-2.881]), and inguinal hernia (1.484, [1.189-1.851]) in male infants and CAKUT (1.619, [1.154-2.273]) in female infants, whereas high MBW was associated with congenital heart disease (1.745, [1.058-2.877]) and CAKUT (2.470, [1.350-4.517]) in male infants. The present study is the first to demonstrate a link between MBW and congenital malformations in Japanese children. While these results must be interpreted with caution, MBW should be considered a major predictor of congenital malformation risk.

The impact of maternal and paternal birth weights on infant birth weights: the Japan environment and children's study

This study aimed to evaluate the association between parental and infant birth weights in Japan. In total, 37,504 pregnant Japanese women and their partners were included in this birth cohort study. A multinomial logistic regression model was used to evaluate the associations of parental birth weights with small-for-gestational-age (SGA) or large-for-gestational-age (LGA) infants. Associations between parental birth weight and low birth weight (LBW) infants or macrosomia were also examined, and linear associations between parental birth weight and SGA or LGA were found. The adjusted odds ratios (aORs) for SGA infants per 500 g decrease in maternal and paternal birth weights were 1.50 (95% confidence interval [CI],1.43-1.58) and 1.31 (95% CI, 1.25-1.38), respectively. The aORs for LGA infants per 500 g increase in maternal and paternal birth weights were 1.53 (95% CI, 1.47-1.60) and 1.41 (95% CI, 1.35-1.47), respectively. The association between parental birth weight and LBW infants or macrosomia was also linear. The aORs for LBW infants per 500 g decrease in maternal and paternal birth weights were 1.47 (95% CI, 1.40-1.55) and 1.25 (95% CI, 1.19-1.31), respectively. The aORs for macrosomia per 500 g increase in maternal and paternal birth weights were 1.59 (95% CI, 1.41-1.79) and 1.40 (95% CI, 1.23-1.60), respectively. Parental birth weight was found to be associated with infant birth weight even after adjusting for various parental factors. Furthermore, maternal birth weight was more strongly associated with infant birth weight than with paternal birth weight.

Maternal birth weight as an indicator of early-onset and late-onset hypertensive disorders of pregnancy: The Japan Environment and Children's study

OBJECTIVES

This study aimed to investigate the association between maternal birth weight (MBW) and hypertensive disorders of pregnancy (HDP) according to the gestational age when HDP develops.

STUDY DESIGN

A total of 77,345 subjects were included in this prospective birth cohort study. The association between MBW and HDP was investigated by a multinomial logistic regression model.

MAIN OUTCOME MEASURES

Early-onset HDP (EO-HDP), preterm late-onset HDP (preterm LO-HDP), and term late-onset HDP (term LO-HDP).

RESULTS

Lower MBW was associated with higher odds of preterm and term LO-HDP (p-values for trend < 0.0001 and = 0.0005, respectively). A linear association between MBW and EO-HDP was observed (p-values for trend = 0.0496). The shape of the association between MBW and preterm LO-HDP was a combination of the associations between MBW with EO-HDP or LO-HDP. The effect size of the association between MBW < 2,500 g and EO-HDP was lower than that of MBW < 2,500 g with preterm or term LO-HDP. The adjusted odds ratios for EO-HDP, preterm LO-HDP, and term LO-HDP in subjects with MBW < 2,500 g were 1.052 (95 % confidence interval [CI]: 0.665-1.664), 1.745 (95 % CI: 1.220-2.496), and 1.496 (95 % CI: 1.154-1.939), respectively.

CONCLUSIONS

MBW was associated with HDP, regardless of gestational age when HDP developed. Furthermore, the association of MBW < 2,500 g with preterm or term LO-HDP was stronger than that with EO-HDP.

Difference in risk of preterm and small-for-gestational-age birth depending on maternal occupations in Japan

OBJECTIVES

In this study, an association between the mother's occupations with preterm and small-for-gestational-age (SGA) births was investigated using national data in Japan, and individual-level birth data from the Report of Vital Statistics: Occupational and Industrial Aspects in the 2015 fiscal year were used. Preterm and SGA birth rates were calculated for each of infant characteristics, and relative risk of each type of maternal occupations (categorized into 12 types) for the outcomes was estimated using a log binomial regression model.

RESULTS

Data of 997,600 singleton births were analyzed. Among maternal occupations, preterm birth rate was highest among carrying, cleaning, packaging, and related workers (5.65%) and lowest among security workers (4.24%). SGA birth rate was highest among manufacturing process workers (5.91%) and lowest among security workers (4.00%). We found significantly elevated risks for preterm birth among manufacturing process workers compared with unemployed mothers, and significantly elevated risks for SGA birth compared with unemployed mothers were observed among sales workers, service workers, and manufacturing process workers. In contrast, security workers had a significantly decreased risk for SGA birth compared with unemployed mothers.

Association of maternal birth weight and maternal preterm birth with subsequent risk for adverse reproductive outcomes: The Women's Health Initiative

BACKGROUND

Advancements in medical technology and pharmacologic interventions have drastically improved survival of infants born preterm and low birth weight, but knowledge regarding the long-term health impacts of these individuals is limited and inconsistent.

AIM

To investigate whether an individual's birthweight or history of being born preterm increases the risk of an adverse reproductive outcome.

STUDY DESIGN

Nested case-control study within the Women's Health Initiative.

SUBJECTS

79,934 individuals who self-reported their personal birthweight category and/or preterm birth status.

OUTCOMES MEASURES

Self-reported pregnancy outcomes: subfertility, miscarriage, stillbirth, preeclampsia, gestational diabetes, gestational hypertension, preterm birth, low birthweight infant, high birthweight infant. Logistic regression models were used to estimate unadjusted and adjusted odds ratios (OR).

RESULTS

After adjustments, individuals reporting their birthweight <6lbs. were 20 % more likely to have a stillbirth or 70 % more likely to have a low birthweight infant and were less likely to have a full-term birth or high birthweight infant during their pregnancy. Individuals reporting a birthweight ≥10 lbs. were more likely to have a high birthweight infant (OR 3.49, 95 % CI 2.73-4.39) and less likely to have a low birthweight infant (OR 0.64, 95 % CI 0.47-0.82). Individuals born preterm were at increased risk for infertility, miscarriage, preeclampsia, gestational diabetes, and delivering a preterm or low birthweight infant.

CONCLUSIONS

As more individuals born preterm and/or low birthweight survive to adulthood, the incidence and prevalence of poor reproductive outcomes may increase. Women born at extremes of birthweight and prematurity may need to be monitored more closely during their own pregnancies.

Differences in Rates of Low Birth Weight among Prefectures in Japan: An Ecological Study Using Government Statistics Data

The differences in the rates and trends of the overall low birth weight and term low birth weight in recent years are unknown for the Japanese prefectures. In this ecological study, we revealed the rates for each prefecture and investigated the factors affecting the regional differences in these outcomes. Aggregated vital statistics data from 2007 to 2019 were obtained from the Ministry of Health, Labour, and Welfare in Japan. The association between the outcomes and the variables, including the infants’ birth characteristics, medical characteristics, and socioeconomic characteristics of the prefectures, were analyzed. An analysis of repeated-measures data was conducted using the data from 2013 and 2018 for each prefecture. The trend for the rates of overall low birth weight and term low birth weight over the years differed among the prefectures. Moreover, the proportions of multiple births and lean (body mass index <18.5 kg/m2) and obese (body mass index ≥25.0 kg/m2) women had a statistically significant positive association with both the overall low birth weight rate and the term low birth weight rate among the prefectures. It was suggested that to resolve the difference in these outcomes among the prefectures, being obese or underweight needs to be addressed in mothers.

Maternal and neonatal factors associated with low birth weight among neonates delivered at the University of Gondar comprehensive specialized hospital, Northwest Ethiopia

INTRODUCTION

Low birth weight is a major contributory factor to infant mortality. Although low birth weight remains an important public health problem in Ethiopia, little emphasis is paid to its intervention as a means of reducing neonatal mortality. The aim of this study was to assess the magnitude of low birth weight and its associated maternal and neonatal factors in newborns delivered at the University of Gondar Comprehensive Specialized Hospital.

METHODS

Hospital-based cross-sectional study was conducted, and 481 study participants were selected using systematic random sampling methods. Pre-tested interviewer-administered questionnaires were used to collect the data. Bivariable and multivariable binary logistic regression was implemented. Finally, the odds ratio with a 95% CI and a p-value of <0.05 were used to identify factors associated with low birth weight.

RESULT

The prevalence of low birth weight was 12.5% (95% CI; 9.8, 15.7%). Preterm birth (AOR = 38; 95% CI: 15.3, 93.0), pregnancy-induced hypertension (PIH) (AOR = 2.6; 95%CI: 1.1, 6.4), maternal body mass index (BMI) of < 18.5 kg/m² (AOR = 6.8; 95% CI: 1.5, 31.1), and grand multiparity (AOR = 4.2; 95% CI: 1.2, 16) were factors positively associated with low birth weight. However, babies delivered from mothers with age > 35 years (AOR = 0.14:95% CI 0.03, 0.7) had lower odds of low birth weight.

CONCLUSION

In this study, the prevalence of low birth weight was higher than in the previous studies. The study revealed preterm birth, PIH, BMI of < 18.5 kg/m², and grand multiparity were independent factors that increase the low birth weight while maternal age > 35 years reduces the low birth weight. Therefore, healthcare professionals should emphasize the early identification and management of women with PIH, tackling prematurity, and preventing maternal malnutrition through nutritional counseling as much as possible.