Effect of gestational weight gain on preeclampsia among underweight women: A single tertiary referral center study in Japanese women

Predicting postpartum hemorrhage in women undergoing planned cesarean section: A multicenter retrospective cohort study in Japan

Given Japan's unique social background, it is critical to understand the current risk factors for postpartum hemorrhage (PPH) to effectively manage the condition, especially among specific groups. Therefore, this study aimed to identify the current risk factors for PPH during planned cesarean section (CS) in Japan. This multicenter retrospective cohort study was conducted in two tertiary maternal-fetal medicine units in Fukushima, Japan and included 1,069 women who underwent planned CS between January 1, 2013, and December 31, 2022. Risk factors for PPH (of > 1000 g and > 1500 g) were assessed using multivariate logistic regression analysis, considering variables such as maternal age, parity, assisted reproductive technology (ART) pregnancy, pre-pregnancy body mass index (BMI), uterine myoma, placenta previa, gestational age at delivery, birth weight categories, and hypertensive disorders of pregnancy (HDP). Multivariate linear regression analyses were conducted to predict estimated blood loss during planned CS. ART pregnancy, a pre-pregnancy BMI of 25.0-29.9 kg/m2, and uterine myoma increased PPH risk at various levels. Maternal smoking increased the risk of >1500 g PPH (adjusted odds ratio: 3.09, 95% confidence interval [CI]: 1.16-8.20). Multivariate linear analysis showed that advanced maternal age (B: 83 g; 95% CI: 27-139 g), ART pregnancy (B: 239 g; 95% CI: 121-357 g), pre-pregnancy BMI of 25.0-29.9 kg/m2 (B: 74 g; 95% CI: 22-167 g), uterine myoma (B: 151 g; 95% CI: 47-256 g), smoking (B: 107 g; 95% CI: 13-200 g), and birth weight > 3,500 g (B: 203 g; 95% CI: 67-338 g) were associated with blood loss during planned CS. Considering a patient's clinical characteristic may help predict bleeding in planned CSs and help improve patient safety.

Physical activity during pregnancy and its relationship with gestational weight gain

Objective: to describe the physical activity patterns of a cohort comprised by pregnant women from our environment and to explore its association with weight gain in each of the trimesters of pregnancy. Methods: a descriptive and longitudinal study conducted with a sample of 151 women. The International Physical Activity Questionnaire was used to assess physical activity during pregnancy based on volume, intensity and setting where it is performed. Different multiple linear regression models were performed to analyze the association between physical activity and gestational weight gain Results: physical activity decreased during pregnancy, both in terms of time and intensity. Pre-gestational Body Mass Index was the main factor associated with lower weight gain throughout pregnancy. The influence of physical activity on gestational weight gain was limited to the third trimester of pregnancy, where an inverse association was observed between both variables. Conclusion: the results of this study show an important reduction in physical activity during pregnancy and suggest that it exerts a limited influence on gestational weight gain

Atividade física durante a gestação e sua relação com o ganho de peso gestacional

Objetivo: descrever os padrões de atividade física de uma coorte de gestantes em nosso meio e explorar sua associação com o ganho de peso em cada um dos trimestres de gestação. Método: estudo descritivo longitudinal com uma amostra de 151 mulheres. O Questionário Internacional de Atividade Física foi utilizado para avaliar a atividade física durante a gestação de acordo com o volume, intensidade e escopo do desempenho. Diferentes modelos de regressão linear múltipla foram utilizados para analisar a associação entre atividade física e ganho de peso gestacional. Resultados: a atividade física diminuiu durante a gestação, tanto em tempo quanto em intensidade. O índice de massa corporal pré-gestacional foi o principal fator associado ao menor ganho de peso ao longo da gestação. A influência da atividade física no ganho de peso gestacional limitou-se ao terceiro trimestre de gestação, no qual foi observada associação inversa entre ambas as variáveis. Conclusão: os resultados deste estudo mostram uma diminuição significativa da atividade física no momento da gravidez e sugerem uma influência limitada desta no ganho de peso gestacional.

Comparison of the 2009 Institute of Medicine and 2021 Chinese guidelines for gestational weight gain: A retrospective population-based cohort study

OBJECTIVE

To analyze the associations between gestational weight gain (GWG) and perinatal outcomes based on the GWG guidelines of the Chinese Nutrition Society (CNS) and the Institute of Medicine (IOM).

METHODS

This was a retrospective study with 9075 low-risk singleton pregnant women. Logistic regression model was used to analyze associations between GWG categories and perinatal outcomes. Sensitivity analyses were performed based on pre-pregnancy body mass index (calculated as weight in kilograms divided by the square of height in meters).

RESULTS

Excessive GWG as defined by the two guidelines was associated with a higher risk of adverse perinatal outcomes. Inadequate GWG was associated with higher risks of small for gestational age (adjusted odds ratio [aOR] 1.34, 95% confidence interval [CI] 1.10-1.64) and preterm birth (aOR 1.70, 95% CI 1.22-2.36), but a lower risk of large for gestational age (LGA) (aOR 0.77, 95% CI 0.63-0.95) according to the IOM guidelines. When using the CNS guidelines, inadequate GWG was associated with only a lower risk of preterm birth (aOR 1.80, 95% CI 1.19-2.70). Sensitivity analyses suggested that excessive GWG was associated with a higher risk of LGA in underweight women.

CONCLUSIONS

Both guidelines could demonstrate the relationship between GWG and adverse perinatal outcomes. The CNS guidelines were more suitable for the Chinese population with underweight or normal weight before pregnancy, whereas IOM was more suitable for pregnant women with inadequate GWG.

Association between Gestational Weight Gain and Risk of Hypertensive Disorders of Pregnancy among Women with Obesity: A Multicenter Retrospective Cohort Study in Japan

The relationship between weight gain during pregnancy and the onset of hypertensive disorders of pregnancy in women with pre-pregnancy obesity remains unclear. We examined the effects of weight gain during pregnancy on hypertensive disorders of pregnancy among women with pre-pregnancy body mass index (BMI) ≥ 25.0 kg/m². This multicenter retrospective cohort study included nullipara women who delivered at two units in Japan between 1 January 2013, and 31 December 2020. Singleton primipara (n = 3040) were categorized into two pre-pregnancy BMI groups: 25.0-<30.0, and ≥30.0 kg/m². Using multiple logistic regression analyses (reported as adjusted odds ratio and 95% confidence interval), gestational weight gain effects on overall hypertensive disorders of pregnancy, gestational hypertension, and pre-eclampsia were determined. Gestational weight gain increased hypertensive disorders of pregnancy (1.09, 1.03-1.16, p < 0.05) and pre-eclampsia risk (1.10, 1.01-1.20, p < 0.05) among the BMI 25.0-<30.0 kg/m² group and hypertensive disorders of pregnancy risk among the ≥30.0 kg/m² group (1.07, 1.00-1.05, p < 0.05). Using receiver operating characteristic curve analyses, among the BMI 25.0-<30.0 kg/m² group, for hypertensive disorders of pregnancy (area under the curve [AUC], 0.63, p < 0.05) and pre-eclampsia (AUC, 0.62; p < 0.05), the weight gain cut-off was 10.5 and 10.6 kg, with sensitivity/specificity of 0.47/0.73 and 0.50/0.73, respectively. For the BMI ≥30.0 kg/m² group (AUC, 0.63, p < 0.05), the cut-off was 3.5 kg (sensitivity/specificity, 0.75/0.49). The optimal gestational weight gain for reducing hypertensive disorders of pregnancy among women with a pre-pregnancy BMI > 25 kg/m² may facilitate personalized pre-conception counseling among women with obesity.

Physical activity during pregnancy and its relationship with gestational weight gain

OBJECTIVE

to describe the physical activity patterns of a cohort comprised by pregnant women from our environment and to explore its association with weight gain in each of the trimesters of pregnancy.

METHODS

a descriptive and longitudinal study conducted with a sample of 151 women. The International Physical Activity Questionnaire was used to assess physical activity during pregnancy based on volume, intensity and setting where it is performed. Different multiple linear regression models were performed to analyze the association between physical activity and gestational weight gain.

RESULTS

physical activity decreased during pregnancy, both in terms of time and intensity. Pre-gestational Body Mass Index was the main factor associated with lower weight gain throughout pregnancy. The influence of physical activity on gestational weight gain was limited to the third trimester of pregnancy, where an inverse association was observed between both variables.

CONCLUSION

the results of this study show an important reduction in physical activity during pregnancy and suggest that it exerts a limited influence on gestational weight gain.

Gestational weight gain as a risk factor for dystocia during first delivery: a multicenter retrospective cohort study in Japan

Background

Dystocia is a common obstetric complication among nulliparous women, which requires medical intervention and carries the risk of negative maternal and neonatal outcomes. Our aim was to examine the association between body mass index (BMI) and the occurrence of dystocia. We also identified cutoffs of gestational weight gain, based on pre-pregnancy BMI, associated with the risk of dystocia.

Methods

This was a multicenter, retrospective, cohort study conducted in two tertiary Maternal–Fetal medicine units in Fukushima, Japan. The study population included nullipara women who delivered at either of the two units between January 1, 2013, and December 31, 2020. Women (n = 2597) were categorized into six groups (G) based on their pre-pregnancy BMI: G1 (< 18.5 kg/m²), G2 (18.5 to < 20.0 kg/m²), G3 (20.0 to < 23.0 kg/m²), G4 (23.0 to < 25.0 kg/m²), G5 (25.0 to < 30.0 kg/m²), and G6 (≥ 30.0 kg/m²). Using G3 as a reference, multiple logistic regression analyses were performed to estimate the risk of dystocia for each BMI category. Receiver operating characteristic curve analyses were performed to determine the cutoff value of gestational weight gain for the risk of dystocia.

Results

The highest BMI category (G6) was an independent risk factor for dystocia (adjusted odds ratio, 3.0; 95% confidence interval, 1.5–5.8). The receiver operating characteristic curve analysis revealed no association between gestational weight gain and the occurrence of dystocia in G5 and G6 (P = 0.446 and P = 0.291, respectively). For G1 to G4, AUC and predictive cutoffs of gestational weight gain for dystocia were as follows: G1, AUC 0.64 and cutoff 11.5 kg (P < 0.05); G2, AUC 0.63 and cutoff 12.3 kg (P < 0.05); G3, AUC 0.67 and cutoff 14.3 kg (P < 0.01); and G4, AUC 0.63 and cutoff 11.5 kg (P < 0.05).

Conclusion

A pre-pregnancy BMI > 30.0 kg/m² was an independent risk factor for dystocia. For women with a pre-pregnancy BMI < 25.0 kg/m², the risk of dystocia increases as a function of gestational weight gain. These findings could inform personalized preconception care for women to optimize maternal and neonatal health.

Risk of preeclampsia by gestational weight gain in women with varied prepregnancy BMI: A retrospective cohort study

INTRODUCTION

Despite the important clinical significance, limited data on the joint contribution of prepregnancy body mass index (BMI) and gestational weight gain (GWG) to preeclampsia, the second leading cause of maternal mortality worldwide. This study aimed to estimate the risk of preeclampsia by GWG among women with varied prepregnancy BMI.

METHODS

We conducted a retrospective cohort study using data of 117 738 singleton pregnant women aged 18-49 years from 150 maternity hospitals in China between 2015 and 2018. GWG was calculated as the measured weight at the time of preeclampsia assessment minus prepregnancy weight; GWG velocity was calculated as the GWG divided by the gestational age at weighing. The non-linear associations of GWG with preeclampsia were examined by restricted cubic spline regression analysis according to prepregnancy BMI. The association of the GWG categories with preeclampsia was further examined by performing robust Poisson regression stratified by the prepregnancy BMI categories.

RESULTS

Among participants, 2426 (2.06%) were diagnosed with preeclampsia. Compared to women with normal BMI, those who were overweight and obese had 1.92- fold (95%CI, 1.73-2.14) and 5.06- fold (95%CI, 4.43-5.78) increased risks for preeclampsia, respectively. The association of GWG velocity with preeclampsia was presented as a J-shaped curve with the varied inflexion point (where the rate of preeclampsia was 2%), which was 0.54, 0.38, and 0.25 kg/week in women with normal BMI, overweight, and obesity, respectively; a steep risk rise was observed along with GWG velocity beyond the inflexion points. The overall adjusted relative risk for preeclampsia was calculated among women with the different GWG categories of GWG.

CONCLUSIONS

The findings highlight that high prepregnancy BMI and exceed GWG contributed to increased risk of preeclampsia with a superimposed effect and underscore the need to optimize the recommendations for GWG for women with different prepregnancy BMI.