Study On The Relationship Between Body Composition Changes In Early Pregnancy And Gestational Diabetes

Background:Gestational diabetes（GDM）refers to diabetes that is first diagnosed in the second trimester of pregnancy after a woman has no significant abnormality in glucose metabolism before pregnancy and is one of the most common complications of pregnancy.In 1999,2012 and 2013,the incidence of gestational diabetes in China was2.1%,8.1% and 10.9%,respectively,showing an increasing trend year by year.The current prevalence rate in China is as high as 17.8%.Gestational diabetes not only affects the short-term health of mother and fetus,but also affects the long-term prognosis of mother and child.In pregnancy or childbirth can appear such as giant infants,cesarean section,poor wound healing,prolonged labor,postpartum hemorrhage,neonatal hypoglycemia,fetal intrauterine distress,greater than gestational age,gestational hypertension disease（HDCP）,polyhydramnios,premature rupture of membranes and premature delivery and other recent complications;The risk of type 2diabetes（T2DM）,cardiovascular disease（CVD）and long-term postpartum obesity is increased in pregnant women with postpartum gestational diabetes.Their offspring are more likely to develop obesity and cardiovascular disease in childhood and adolescence than those of women with normal pregnancies.However,gestational diabetes can only be diagnosed at a later time when an oral glucose tolerance test（OGTT）is performed24-28 weeks after gestation.At this time,gestational diabetes has already occurred,and medical staff can only treat it,but not prevent it.To seek better screening methods in early pregnancy to predict the occurrence of gestational diabetes,so as to intervene as early as possible and effectively reduce the adverse effects of gestational diabetes on mothers and children.Existing evidence shows that most pregnant women with gestational diabetes already have hyperglycemia in their bodies during routine pregnancy screening,and there is currently a lack of effective means and methods for early pregnancy screening and identification of gestational diabetes.Excessive weight gain during pregnancy has been shown to be an independent risk factor for gestational diabetes.At present,about 38% of pregnant women gain too much weight during pregnancy in China,of which 47.5% occur in the early stage of pregnancy.The sensitivity of excessive weight gain in the early stage of pregnancy to the occurrence of weight gain and gestational diabetes is 60% and 59%,and the specificity is 87% and53%,respectively.In a prospective cohort study in California,Hedderson et al.found no significant difference in weight gain between the gestational diabetes group and the control group during the second trimester and before gestational diabetes screening.Chinese scholars also found that the incidence of gestational diabetes was not associated with weight gain during the second trimester.Excessive weight gain in late pregnancy is associated with cesarean section.Therefore,weight change in early pregnancy is a critical period for gestational total weight gain,and excessive weight gain in early pregnancy is closely related to the incidence of gestational diabetes.However,there has been no in-depth study on why excessive weight gain in early pregnancy leads to the occurrence of gestational diabetes.Therefore,this study analyzed the correlation between body composition changes in early pregnancy and gestational diabetes,and sought for potential predictors of gestational diabetes in early pregnancy.Objective:1.General data of eligible pregnant women and body composition data of 6-8,11-13,24-28 weeks of gestation were collected.Prospective nested case-control study was used to analyze the correlation between body composition changes in the early and middle stages of pregnancy and gestational diabetes mellitus group and control group.2.After studying the correlation between body composition changes in early pregnancy and gestational diabetes,the influence of body composition during pregnancy on OGTT（fasting,postprandial 1h,2h blood glucose）results was further analyzed.3.Binary Logistic regression was used to explore the risk factors of GDM,and the operating characteristic curves of subjects were drawn to evaluate the possible predictive value of the indexes in body components for GDM.Methods:1.A prospective nested case-control study was conducted to select single pregnant women who underwent regular prenatal check-up and voluntarily received nutritional evaluation in Dongfeng General Hospital,Affiliated to Hubei University of Medicine from September 2020 to September 2021.2.The basic information of pregnant women,such as age,height,weight,pre-pregnancy body mass index（BMI）,birth rate and educational background,was recorded during initial filing.3.The maternal body composition and body composition of the pregnant women who voluntarily received nutritional evaluation were analyzed by bioresistance assay at6 to 8 weeks,11 to 13 weeks and 24 to 28 weeks of gestation.OGTT examination was performed at 24 to 28 weeks of gestation.Pregnant women diagnosed with GDM were included in the GDM group（n=49 cases）,and healthy pregnant women were included in the normal group（n=87 cases）.4.The data of the two groups were statistically analyzed by SPSS 25.0.Results:1.There were no significant differences in extracellular fluid,muscle mass,fat-free weight,body fat percentage,gestational weight gain（GWG）,fat mass index（FMI）and muscle mass index（SMMI）between the two groups at 6-8 weeks of gestation（ALL P >0.05）.2.Comparison of body composition indexes between the two groups at 11 to 13 weeks of gestation: body fat percentage and FMI in GDM group were significantly higher than those in normal group（P < 0.05）,while muscle mass,fat removal weight and SMMI in GDM group were significantly lower than those in normal group（P <0.05）,while there were no statistical differences in extracellular fluid and GWG（P >0.05）.3.There were no significant differences in extracellular fluid,muscle mass,body fat loss weight,body fat percentage,GWG,FMI and SMMI between the two groups at24-28 weeks of gestation（ALL P > 0.05）.4.The relationship between body composition and fasting,1h and 2h postprandial blood glucose at 11 to 13 weeks of pregnancy: Spearman correlation analysis showed that the percentage of body fat in GDM group was significantly positively correlated with fasting blood glucose（R =0.206,P=0.020）,while extracellular fluid,muscle mass,fat loss weight were not significantly correlated with blood glucose in the two groups（P > 0.05）.5.Logistic regression analysis of GDM and body composition index at 11 to 13 weeks of gestate: FMI（OR=0.545,95%CI: 0.350-0.848,P=0.007）,suggesting that GDM is an independent risk factor.6.Predictive value of FMI for GDM: In this study,the area under ROC curve predicted by FMI for GDM was 0.644.When FMI was 5.905,the sensitivity and specificity were 0.85 and 0.586,respectively,and the Yuden index was 0.436.Conclusion:1.Body fat percentage at 11 to 13 weeks of gestation is associated with the risk of GDM.2.Fat mass index in early pregnancy may be an independent predictor of GDM.