Associations between gestational weight gain and preterm birth in Puerto Rico

Association between maternal gestation weight gain and preterm birth according to pre-pregnancy body mass index and HbA1c

BACKGROUND

To investigate the association between gestational weight gain (GWG) and preterm birth (PTB) according to pre-pregnancy body mass index (pp-BMI) and glycated haemoglobin (HbA1c) within the normal range.

METHODS

We conducted a population-based retrospective cohort study between July 2017 and January 2020 at Women's Hospital, Zhejiang University School of Medicine. Women were classified into three groups (inadequate GWG, appropriate GWG, and excessive GWG). In addition, women were divided into different subgroups according to pp-BMI and HbA1c. We estimated the odds ratios (OR) with 95% confidence intervals (CI) to assess the associations between GWG and the risk of PTB. Meanwhile, we adjusted for possible confounding factors, including maternal age, infant sex, family history of diabetes, education, pregnancy mode, delivery mode, parity, and gravidity.

RESULTS

The study involved 23,699 pregnant women, of which 1124 (4.70%) were PTB. Women who had inadequate GWG were found to have a significantly higher risk of PTB compared to women with appropriate GWG. In contrast, women with excessive GWG had a reduced risk of PTB. Similarly, GWG and PTB had similar risk associations in the HbA1c and pp-BMI subgroups. Among women with pp-BMI <18.5 kg/m2, women with inadequate GWG had a significantly increased risk of PTB compared with women in the control group (HbA1c 4.6-5.0%, appropriate GWG), and the risk increased with increasing HbA1c levels. Similar results were observed in women with normal pp-BMI.

CONCLUSIONS

There was a significant association between GWG and the risk of PTB, but the risk varied by pp-BMI and HbA1c levels. Reasonable weight gain during pregnancy is essential to prevent PTB. Furthermore, while HbA1c is within the normal range, the higher levels should be noticed.

Association of prepregnancy body mass index and gestational weight gain trajectory with adverse pregnancy outcomes-a prospective cohort study in Shanghai

OBJECTIVES

The objective was to investigate the associations of maternal prepregnancy body mass index (BMI) and gestational weight gain (GWG) trajectories with adverse pregnancy outcomes (APOs).

DESIGN

This was a prospective cohort study.

SETTING

This study was conducted in Shanghai Pudong New Area Health Care Hospital for Women and Children, Shanghai, China.

PRIMARY AND SECONDARY OUTCOME MEASURES

A cohort study involving a total of 2174 pregnant women was conducted. Each participant was followed to record weekly weight gain and pregnancy outcomes. The Institute of Medicine classification was used to categorise prepregnancy BMI, and four GWG trajectories were identified using a latent class growth model.

RESULTS

The adjusted ORs for the risks of large for gestational age (LGA), macrosomia, gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP) were significantly greater for women with prepregnancy overweight/obesity (OR=1.77, 2.13, 1.95 and 4.24; 95% CI 1.3 to 2.42, 1.32 to 3.46, 1.43 to 2.66 and 2.01 to 8.93, respectively) and lower for those who were underweight than for those with normal weight (excluding HDP) (OR=0.35, 0.27 and 0.59; 95% CI 0.22 to 0.53, 0.11 to 0.66 and 0.36 to 0.89, respectively). The risk of small for gestational age (SGA) and low birth weight (LBW) was significantly increased in the underweight group (OR=3.11, 2.20; 95% CI 1.63 to 5.92, 1.10 to 4.41; respectively) compared with the normal-weight group; however, the risk did not decrease in the overweight/obese group (p=0.942, 0.697, respectively). GWG was divided into four trajectories, accounting for 16.6%, 41.4%, 31.7% and 10.3% of the participants, respectively. After adjustment for confounding factors, the risk of LGA was 1.54 times greater for women in the slow GWG trajectory group than for those in the extremely slow GWG trajectory group (95% CI 1.07 to 2.21); the risk of SGA and LBW was 0.37 times and 0.46 times lower for women in the moderate GWG trajectory group and 0.14 times and 0.15 times lower for women in the rapid GWG trajectory group, respectively; the risk of macrosomia and LGA was 2.65 times and 2.70 times greater for women in the moderate GWG trajectory group and 3.53 times and 4.36 times greater for women in the rapid GWG trajectory group, respectively; and the women in the other three trajectory groups had a lower risk of GDM than did those in the extremely slow GWG trajectory group, but there was not much variation in the ORs. Notably, different GWG trajectories did not affect the risk of HDP.

CONCLUSIONS

As independent risk factors, excessively high and low prepregnancy BMI and GWG can increase the risk of APOs.

Combined effects of pre-pregnancy BMI and gestational weight gain on preterm birth: comparison between spontaneous and ART conception

BACKGROUND

Inappropriate pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are both linked to preterm birth (PTB); however, which one plays a dominant role in PTB risk is not yet sure. We aimed to evaluate the combined effect of pre-pregnancy BMI and GWG on the risk of PTB in singleton pregnancies conceived both spontaneously and through assisted reproductive technology (ART).

METHODS

The data included all mothers (n = 17,540,977) who had a live singleton birth from the US National Vital Statistics System (NVSS) 2015-2019. Logistic regression models, quantile-g-computation, and generalized additive model were used to analyze the combined association of pre-pregnancy BMI and GWG with PTB.

RESULTS

The singleton PTB rate was significantly higher in ART pregnancies (11.5%) than in non-ART pregnancies (7.9%). When compared to those women with pre-pregnancy normal weight and GWG within Institute of Medicine (IOM) guidelines, the highest PTB risk was observed in non-ART women with pre-pregnancy underweight and GWG below IOM guidelines (aOR 2.56; 95% CI 2.53-2.60) and in ART women with pre-pregnancy obese and GWG below IOM guidelines (aOR 2.56; 95%CI 2.36-2.78). GWG dominated the combined effect with its joint effect coefficient of - 0.281 (P < 0.05) in non-ART women and - 0.108 (P < 0.05) in ART women.

CONCLUSIONS

Inappropriate GWG played a dominant role in increasing the risk of PTB in both non-ART and ART populations. Counseling regarding pre-pregnancy BMI and especially GWG appears to be even more crucial for pregnancies conceived via ART, given their impact on PTB.

Association between gestational weight gain and adverse neonatal outcomes in women conceiving with assisted reproductive technology: Evidence from the NVSS 2019-2021

OBJECTIVE

To evaluate the association between gestational weight gain (GWG) and adverse neonatal outcomes in women who conceived using assisted reproductive technology (ART).

METHODS

The National Vital Statistics System (NVSS) 2019-2021 provided data for this retrospective cohort study. Adverse neonatal outcomes included premature birth, small for gestational age (SGA), large for gestational age (LGA), macrosomia, low birth weight (LBW), and other abnormal conditions. Any adverse outcome was defined as at least one of the above six outcomes. Multivariate logistic regression analysis was employed to evaluate the associations between GWG and different outcomes, after adjusting for confounding factors. These associations were further assessed in subgroups of maternal age at delivery, paternal age at delivery, preconception body mass index (BMI), gestational age, maternal race, parity, gestational diabetes, and gestational hypertension.

RESULTS

Totally 108201 women were included, with 22282 in the insufficient GWG group, 38034 in the sufficient GWG group, and 47885 in the excessive GWG group. Women with insufficient GWG [odds ratios (OR) = 1.11, 95%CI: 1.07-1.16, P<0.001] and excessive GWG (OR = 1.14, 95%CI: 1.10-1.18, P<0.001) had significantly greater risks of any adverse outcome than those with sufficient GWG. In contrast to sufficient GWG, insufficient GWG was associated with significantly elevated risks of premature birth (OR = 1.42, 95%CI: 1.35-1.48, P<0.001), SGA (OR = 1.45, 95%CI: 1.37-1.53, P<0.001), LBW (OR = 1.47, 95%CI: 1.37-1.58, P<0.001), and other abnormal conditions (OR = 1.32, 95%CI: 1.27-1.39, P<0.001), and excessive GWG was associated with significantly lower risks of premature birth (OR = 0.86, 95%CI: 0.83-0.90, P<0.001), SGA (OR = 0.79, 95%CI: 0.75-0.83, P<0.001), LBW (OR = 0.85, 95%CI: 0.79-0.91, P<0.001), and other abnormal conditions (OR = 0.92, 95%CI: 0.88-0.96, P<0.001). Infants born to women with insufficient GWG had significantly decreased risks of LGA (OR = 0.71, 95%CI: 0.66-0.75, P<0.001) and macrosomia (OR = 0.68, 95%CI: 0.63-0.74, P<0.001), and infants born to women with excessive GWG had significantly increased risks of LGA (OR = 1.50, 95%CI: 1.44-1.56, P<0.001) and macrosomia (OR = 1.60, 95%CI: 1.51-1.69, P<0.001).

CONCLUSION

Insufficient GWG and excessive GWG were associated with increased risks of any adverse outcome than sufficient GWG in women who conceived with ART, indicating the applicability of recommended GWG by the Institute of Medicine (IOM) in this population.

The association between maternal HbA1c and adverse outcomes in gestational diabetes

BACKGROUND

The role of HbA1c in women with gestational diabetes mellitus (GDM) is still unclear, particularly in the Asian population.

AIM

To investigate the association between HbA1c levels and adverse outcomes considering maternal age, pre-pregnancy body mass index (BMI), and gestational weight gain (GWG) in women with GDM.

METHOD

A retrospective study included 2048 women with GDM and singleton live births. Using logistic regression, the associations between HbA1c and adverse pregnancy outcomes were assessed.

RESULT

Compared to women with HbA1c ≤ 5.0%, HbA1c was significantly associated with macrosomia (aOR 2.63,95%CI1.61,4.31), pregnancy-induced hypertension (PIH, aOR 2.56,95%CI1.57,4.19), preterm birth (aOR 1.64,95%CI 1.05,2.55), and primary Cesarean section (primary C-section, aOR1.49,95%CI1.09,2.03) in GDM women with HbA1c ≥5.5% while significantly associated with PIH (aOR 1.91,95%CI1.24,2.94) in women with HbA1c 5.1-5.4%. The associations between HbA1c and adverse outcomes varied with maternal age, pre-pregnancy BMI, and GWG. In women aged ≤29 years, there's significant association between HbA1c and primary C-section when HbA1c was 5.1-5.4% and ≥5.5%. In women aged 29-34 years and HbA1c ≥5.5%, HbA1c was significantly associated with macrosomia. In women aged ≥35 years, there's significant association between HbA1c and preterm birth when HbA1c was 5.1-5.4% and macrosomia and PIH when HbA1c ≥5.5%. In pre-pregnant normal-weight women, HbA1c was significantly associated with macrosomia, preterm birth, primary C-section, and PIH when HbA1c ≥5.5% while HbA1c was significantly associated with PIH when HbA1c was 5.1-5.4% . In pre-pregnant underweight women with HbA1c 5.1-5.4%, HbA1c was significantly associated with primary C-section. HbA1c was significantly associated with macrosomia among women with inadequate GWG or excess GWG and HbA1c≥5.5%. In women with adequate GWG, there's significant association between HbA1c and PIH when HbA1c was 5.1-5.4% and ≥5.5% .

CONCLUSION

Conclusively, HbA1c at the time of diagnosis is significantly associated with macrosomia, preterm birth, PIH, and primary C-section in Chinese women with GDM.

Gestational Weight Gain Below Instead of Within The Guidelines per Class of Maternal Obesity: A Systematic Review and Meta-Analysis of Obstetrical and Neonatal Outcomes

OBJECTIVE

To systematically investigate a wide range of obstetrical and neonatal outcomes with respect to gestational weight gain (GWG) below the current IOM and ACOG guidelines compared to within the guidelines and to stratify outcomes by the class of obesity and by the type of study analysis.

DATA SOURCES

We systematically searched studies on PubMed, Scopus, Embase, and Cochrane Library from 2009 to April 30, 2021.

STUDY ELIGIBILITY CRITERIA

Studies reporting on obstetrical and neonatal outcomes of singleton pregnancies with respect to GWG below the current IOM and ACOG guidelines compared to within the guidelines, investigated in obesity overall (BMI> 30 kg/m²), and/or class of obesity (I: BMI 30-34.9 kg/m², II: BMI 35-39.9 kg/ m² and III: BMI> 40 kg/m²).

METHODS

Among the studies that met criteria, multiple obstetrical and neonatal outcomes were tabulated and compared between pregnancies with weight gain below the guidelines and those with weight gain within the guidelines, further classified by the class of obesity if applicable. Primary outcomes included small for gestational age (SGA), large for gestational age (LGA), preeclampsia (PE), and gestational diabetes mellitus (GDM). Secondary outcomes included cesarean section (CS), preterm birth (PTB), postpartum weight retention, and composite neonatal morbidity. Meta-analysis of univariate and adjusted multivariate analysis studies were conducted. The random-effect model was used to pool the mean differences or odds ratios (OR) and the corresponding 95% confidence intervals (CIs). Heterogeneity was assessed using the I² value. Newcastle Ottawa Scale (NOS) was used to assess individual study quality.

RESULTS

Total of 54 studies reporting on 30,245,946 pregnancies were included, of which 11,515,411 pregnancies were in the univariate analysis and 18,730,535 pregnancies in the adjusted multivariate analysis. In the meta-analysis of univariate studies, compared to women who gained within the guidelines, those who gained below the guidelines had higher odds for SGA in obesity class I and II (OR:1.30 (95% CI 1.17, 1.45), I² 0%, P<0.00001, and OR: 1.56 (95% CI 1.31, 1.85), I² 0%, P<0.00001), respectively), however, the incidence of SGA was below the expected limits (<10%) and was not associated with increased neonatal morbidity. Furthermore, after adjusting for covariates, that difference was no statistically significant anymore. The difference was not statistically significant for class III obesity. Following adjusted multivariate analysis, no significant differences in SGA rates were noted for all classes of obesity between groups. Significantly lower odds for LGA were seen in GWG below guidelines in obesity class I, II, and III (OR: 0.69 (95% CI 0.64, 0.73), I² 0%, P<0.00001, OR: 0.68 (95% CI 0.63, 0.74), I² 0%, P<0.00001, and OR: 0.65 (95% CI 0.57, 0.75), I² 34%, P<0.00001, respectively), and similar findings were seen in the adjusted multivariate analysis. Women with weight gain below guidelines had significantly lower odds for PE in obesity class I, II, and III (OR: 0.71 (95% CI 0.63, 0.79),), I² 0%, P<0.00001, OR: 0.82 (95% CI 0.73, 0.91), I² 0%, P<0.00001, and OR: 0.82 (95% CI 0.70, 0.94), I² 0%, P=0.006, respectively), and similar findings were seen in the adjusted multivariate analysis. No significant differences were seen in GDM between groups. Regarding PTB, available univariate analysis studies only reported on overall obesity and mixed iatrogenic and spontaneous PTB showing significant increase in the odds of PTB (OR: 1.42 (95% CI 1.40, 1.43), I² 0%, P<0.00001) in women with low weight gain, while adjusted multivariate studies in overall obesity and in all three classes and showed no significant differences of PTB between groups. Women with low weight gain had significantly lower odds for CS in obesity class I, II, and III (OR: 0.76 (95% CI 0.72, 0.81), I² 0%, P<0.00001, OR: 0.82 (95% CI 0.77, 0.87), I² 0%, P<0.00001, and OR: 0.87 (95% CI 0.82, 0.91), I² 0%, P<0.00001, respectively), and similar findings were seen in the adjusted multivariate analysis. There was significantly lower odds for postpartum weight retention (OR: 0.20 (95% CI 0.05, 0.82)), I² 0%, P=0.03) and lower odds for composite neonatal morbidity in the overall obesity group with low GWG (OR: 0.93 (95% CI 0.87, 0.99)), I² 19.6%, P=0.04).

CONCLUSION

Contrary to previous reports, the current systematic review and meta-analysis showed no significant increase in SGA rates in pregnancies with weight gain below the current guidelines for all classes of maternal obesity. Furthermore, gaining below the guidelines was associated with lower LGA, PE, and CS rates. Our study provides the evidence that the current recommended GWG is high for all classes of obesity. These results provide pertinent information supporting the notion to revisit the current GWG recommendations for women with obesity and furthermore to classify them by the class of obesity rather than one overall obesity category as is done in the current recommendations.

When husband migrate: effects of international migration of husbands on fetal outcomes, body mass index and gestational weight of female spouses that stay behind

BACKGROUND

International labour migration continues to be an integral component in Sri Lanka's economic development. Previous research indicates an adverse perinatal outcome in association with low maternal pre-pregnancy body mass index (PBMI) and gestational weight gain (GWG). However, evidence of this association is limited in migrant families. This study aims to investigate the associations between PBMI, GWG among lactating mothers (LM), and fetal outcomes in migrant households, where the father is the migrant worker.

METHODS

A secondary data analysis was done using a nationally representative sample of 7,199 LM. There were 284 LM whose husbands were international migrant workers. Maternal factors were taken as PBMI<18.5 kg/m² and GWG<7kg. Preterm birth and low birth weight (LBW) were taken as fetal outcomes. Binary logistic regression was performed to assess the associated factors.

RESULTS

There was significant difference between LM from migrant and non-migrant households with regards to place of residency, ethnicity, household monthly income, household food security, average household members, husband's education and husband's age. Among migrant, PBMI<18.5 kg/m² was associated with current BMI and mode of delivery. Migrant LM had significantly higher weight gain (≥12 kg) during pregnancy (p=0.005), were multiparous (p=0.008), delivered in private hospital (p=0.000), lesser percentage of underweight (p=0.002) and higher birthweight (p=0.03) than non-migrant LM. Logistic regression model revealed that for each kilogram increment in birthweight and GWG, preterm delivery decreased by 89%(OR=0.11;95%CI:0.04-0.28) and LBW decreased by 12%(OR=0.89;95%CI:0.81-0.97) respectively. Caesarean deliveries were positively associated with low GWG.

CONCLUSION

Our study showed LM in migrant families had invested remittances to utilize private health facilities for deliveries, to improve weight gain during pregnancy and adequate PBMI to deliver higher birth weight babies. In depth study is needed to understand further utilisation of remittances to improve fetal outcomes by increasing birthweight and GWG in migrant families.

Body Mass Index and Gestational Weight Gain Are Associated with Maternal and Neonatal Outcomes Based on Chinese Women

The objective of the study is to analyze the association between early pregnancy body mass index (BMI), gestational weight gain (GWG), and maternal and neonatal outcomes. The retrospective cohort study was conducted at Quanzhou First Hospital Affiliated to Fujian Medical University from January 2018 to May 2021, with 552 women enrolled. Women were divided into the underweight group, normal weight group, overweight group, and obese group according to early pregnancy BMI. Univariate and multivariate logistic regression analyses were performed. The absolute risk of adverse maternal and neonatal outcomes in the early pregnancy BMI group was calculated to further analyze the association between GWG and adverse maternal and neonatal outcomes. Of the 552 women, 390 (70.65%) women had adverse maternal and neonatal outcomes. The result revealed that overweight was associated with increased risk of adverse maternal and neonatal outcomes (odds ratio (OR): 1.643, 95% confidence interval (CI): 1.006-2.684), maternal complications (OR: 1.937, 95% CI: 1.188-3.159), and large for gestational age (LGA) (OR: 1.905, 95% CI: 1.061-3.422). In the obese group, the risk of adverse maternal and neonatal outcomes (OR: 5.760, 95% CI: 1.997-16.786), maternal complications (OR: 3.112, 95% CI: 1.645-5.887), gestational diabetes mellitus (GDM) (OR: 2.943, 95% CI: 1.509-5.741), cesarean section (OR: 1.899, 95% CI: 1.002-3.599), and preterm delivery (OR: 4.752, 95% CI: 1.395-16.185) increased. Besides, there was an association between insufficient GWG and decreased risk of LGA (OR: 0.392, 95% CI: 0.187-0.826) and higher risk of preterm delivery (OR: 2.818, 95% CI: 1.171-6.784). This study demonstrates that BMI and GWG are related to maternal and neonatal outcomes. It is necessary to regularly monitor the weight of pregnant women during pregnancy. And regional guidelines for GWG also need to be explored.