Optimal Gestational Weight Gain for Tibetans Based on Prepregnancy Body Mass Index

Abstract

We aimed to estimate the optimal gestational weight gain (GWG) in tibetan women and to evaluate the appropriateness of the institute of Medicine (ioM) GWG recommendations for tibetan women. We analyzed data from 1474 Tibetan women from a cross-sectional study conducted in 2019. According to the three different body mass index (BMI) classification criteria (WHO BMI categories, WHO Asian BMi categories, chinese BMi categories), we estimated the association of GWG with pregnancy outcomes (neonate birthweight and mode of delivery) using a polynomial regression model, and the optimal GWG in each BMI group was calculated. The risk of adverse outcomes showed a U-shaped curve with increasing GWG. The optimal GWG of Tibetan women based on the WHO BMI categories was 17.2 kg (range, 13.3 to 20.9 kg) for underweight, 9.3 kg (5.8 to 12.9 kg) for normal weight, and 5.2 kg (1.3 to 9.1 kg) for overweight. Underweight Tibetan mothers may gain more gestational weight than recommend by the IOM guidelines. However, normal weight Tibetan mothers are likely to benefit from gaining less weight than that recommended by the ioM. the GWG recommendations based on the ioM guidelines might not be appropriate for Tibetan women, and ethnicity-specific recommendations for GWG should be properly addressed. Prepregnancy body mass index (BMI) and gestational weight gain (GWG) have been known as robust predictors of pregnancy outcomes of the mother and offspring. Excessive GWG is associated with additional adverse health risks, including a greater risk of gestational hypertension, gestational diabetes mellitus, postmature birth, cesarean section, and macrosomia. In contrast, low prepregnancy BMI and inadequate GWG have been linked to small-for-gestational-age infants and premature birth 1-6. Therefore, appropriate GWG, in addition to proper prepregnancy BMI, has been repeatedly shown to be important to optimize pregnancy outcomes. Over the past 60 years, the optimal GWG recommendations have been revised several times due to changes in the demographic and nutrition statuses of women in the United States 7-10. In 2009, the Institute of Medicine (IOM) published the latest revised GWG guidelines based on the World Health Organization (WHO) BMI categories and recommended an optimal GWG of 12.5~18.0 kg for underweight pregnant women (prepregnancy BMI < 18.5 kg/m 2), 11.5~16.0 kg for normal weight pregnant women (prepregnancy BMI 18.5-24.9 kg/m 2), 7.0~11.5 kg for overweight pregnant women (prepregnancy BMI 25.0~29.9 kg/m 2) and 5~9.1 kg for obese pregnant women (prepregnancy BMI ≥ 30 kg/m 2). The guidelines also recommended the ranges of GWG for the second and third trimesters 10. Although the current 2009 IOM GWG guidelines are more rigorous and complete than the previous guidelines, the recommendations were primarily based on Caucasian women; thus, they were more appropriate in the United States and Europe. Therefore, their generalizability has always been controversial worldwide. Moreover, some researchers believe that the 2009 IOM recommendations do ...

Gestational weight gain and pregnancy outcomes: Findings from North Indian pregnancy cohort

“…We found that the mean GWG rate was higher and prevalence of GWG below the IOM guidelines was lower during the second and third trimesters than those in other low‐income countries (Abdulmalik et al, 2019 ; Asefa et al, 2020 ; Bhavadharini et al, 2017 ; Chen, Zhou, et al, 2020 ; Gondwe et al, 2018 ; Hasan et al, 2018 ; Kac et al, 2019 ; Tran et al, 2019 ). In Bangladesh, the mean GWG from enrolment to 36 weeks was 6.5 kg, and 74% of the pregnant women had GWG below the IOM guidelines (Kac et al, 2019 ).…”

Maternal diet and interactions with nutritional evaluation during pregnancy

“…Comparative studies on weight gain assessment between IOM recommendations and Chinese National Guidelines have been corroborated. The conclusion was that results were better when using lower cut‐off points for overweight and obese Asian women and contributed to the recommendation of adequate weight gain in pregnancy 20,21 . In the United Kingdom, the National Institute for Health and Care Excellence guideline recommends that weight is assessed and monitored to prevent obesity and overweight; first measurements of height and weight, and calculation of BMI can be done at the first prenatal appointment at 5 weeks 22…”

“…The conclusion was that results were better when using lower cut-off points for overweight and obese Asian women and contributed to the recommendation of adequate weight gain in pregnancy. 20,21 In the United Kingdom, the National Institute for Health and Care Excellence guideline recommends that weight is assessed and monitored to prevent obesity and overweight; first measurements of height and weight, and calculation of BMI can be done at the first prenatal appointment at 5 weeks. 22 In Brazil, nutritional status is classified by a mixed system: the curve of Atalah et al 23 and IOM guidelines 24 with the pregestational weight, which is also used when initial weight information is missing.…”

Association between weight gain during 24 gestational weeks and pregnancy outcomes: A retrospective study in Chinese population

“…A systematic review and meta-analysis including over 1 million pregnant women suggested that GWG was above the IOM recommended weight gain range in 47% of pregnancies and 23% of pregnant women had GWG less than IOM recommendations(8). Despite the prevalence of IOM guideline, the recommendations cannot be applicable all over the world mainly due to different ethnicities and lifestyles (13).…”