Study On The Gestational Weight Gain In Chinese Women

Objective:(1)One of the aim of this study is to describe the gestational weight gain(GWG)of the Chinese pregnant women;(2)To compare the incidence of adverse pregnancy outcomes between pregnant women with optimal GWG determined by different BMI classifications;(3)To examine whether GWG ranges recommended by IOM is suitable for Chinese population by describing the distributing of maternal GWG in China,and provide data references for improving the strategy of Chinese women GWG management.Method:(1)Firstly,the pregnant women with optimal pregnancy outcomes(healthy pregnant women)among all of the recruited subjects were selected.The analysis of variance(ANOVA)or the Student-Newman-Keuls(SNK)test was used to compare the GWG distribution;drawing the percentile curve charts according to different pre-pregnancy weight status for comparisons to the GWG IOM recommendations.(2)Secondly,pregnant women with optimal GWG according to the different BMI cut-off points were selected.Pregnant women with appropriate GWG according to IOM BMI classification scheme were selected as control group,and women with optimal GWG according tothe Asian BMI classification scheme were exposed group.Comparing adverse pregnancy outcomes between groups with optimal GWG,and the odds ratio(OR)and 95% confidence interval(CI)were calculated,logistic regression model was used to calculate the adjusted OR.Results:1 Total of 16780 were enrolled in this study,of them,13717 births with an optimal pregnancy outcome.And the mean GWG of healthy pregnant women was 14.4±5.39 kg,the minimum GWG was-4.5kg,the maximum was 48.5kg.GWG was found to vary significantly by age,parity,year of education and smoking during pregnancy(P<0.001).When Asian BMI classification criteria were adopted,the GWG decreased with the pre-pregnancy BMI of pregnant women increased.Based on the IOM BMI classification scheme,the relationship between mean GWG and pre-pregnancy BMI of pregnant women followed a U-shaped curve.In the both two types of BMI classification schemes,the ranges of GWG recommended by IOM are within 70%(Pc 15th-Pc 85th)of the observed distributions of healthy pregnant women.(2)Total of 6438 pregnant women with appropriate GWG according to IOM BMI classification scheme were selected as control group,and6110 women with optimal GWG according to the Asian BMI classification scheme were selected as exposed group.Compared with control group,exposed group had lower risks of both macrosomia(crudeOR=0.79,95%CI: 0.67,0.94)and large for gestational age(LGA)(crude OR=0.86,95%CI: 0.76,0.97).After adjustments for confounders,the lower risks of both macrosomia(adjusted OR=0.79,95%CI: 0.67,0.94)and LGA(adjusted OR=0.86,95%CI: 0.76,0.98)still significantly exist.No significantly different risks of having preterm,low birth weight(LBW)or small for gestational age(SGA)or having pregnancy-induced hypertension(PIH)or gestational diabetes mellitus(GDM)were found in our analysis(P>0.05).Conclusions:(1)Our results suggest that the GWG ranges recommended by the Chinese Association of Obstetricians and Gynecologists is still within the Pc 15 th to Pc 85 th of the actual GWG distribution of pregnant women in my country,that is,the middle 70%distribution.(2)Using the Asian BMI cut-off points to monitor and make GWG recommendations to Chinese women can prevent multiple adverse pregnancy outcomes,such as macrosomia and LGA.(3)It is recommended to use the Asian BMI cut-off points to guide the suitable range of GWG for Chinese women.