Effect of early vitamin D supplementation on the incidence of preeclampsia in primigravid women
Objective This study aims to evaluate the effect of vitamin D supplementation in the earliest stages of pregnancy(12-16 weeks)on the development of preeclampsia(PE)in primiparous women.Methods Primiparous women who visited Maternal and Child Care Center of Qinhuangdao from January 1,2019 to January 31,2022 were recruited as study subjects.According to the random number table method,primiparous women were randomly divided into the control group(calcium carbonate D3 tablets)and the experimental group(calcium carbonate D3 tablets+vitamin D).The main observed outcome of the study was the incidence of preeclampsia.Preterm birth,neonatal birth weight,neonatal height at birth,mode of delivery,and neonatal Apgar scores were the secondary observed outcomes.A Logistic regression was used to explore the relationship between vitamin D supplementation and study outcomes.In addition,serum 25 hydroxyvitamin D was measured by ELISA before and after the intervention.Results A total of 586 primiparas were recruited,70 were lost,and 516 were included(264 in the control group and 252 in the experimental group).The incidences of PE,preterm birth,cesarean birth,and birth weight in the experimental group were significantly lower than those of the control group(P<0.05).After the end of the intervention,the serum level of 25 hydroxyvitamin D had increased significantly in both groups(P<0.05),while there was no significant change in calcium ions(P>0.05).Furthermore,serum 25 hydroxyvitamin D levels were significantly higher in the experimental group than in the control group(P<0.05).In addition,the birth length,1-minute Apgar,5-minute Apgar and 10-minute Apgar scores of the experimental group were all higher than the control group(P<0.05).Multivariate Logistic analysis showed that vitamin D supplementation was the independent protective factor for PE[OR=0.336,95%CI(0.120,0.939),P=0.037],cesarean section[OR=0.539,95%CI(0.364,0.798),P=0.002],misoprostol-induced delivery[OR=0.066,95%CI(0.009,0.504),P=0.009],preterm birth[OR=0.487,95%CI(0.238,0.995),P=0.048]and low birth weight[OR=0.391,95%CI(0.189,0.806,P=0.011].Conclusion Vitamin D supplementation reduces the incidence of PE and reduces the incidence of adverse pregnancy and fetal outcomes.