The Relationship Between BMI Before Pregnancy And Gestational Weight Gain During Gestational Hypertension

Objective:1.To explore the relationship between pre-pregnancy body mass index(BMI),weight gain during pregnancy and the development of gestational hypertension;2.To explore the relationship between overweight or obesity before pregnancy,excessive gestational weight gain and the occurrence of pre-eclampsia and severe pre-eclampsia,so as to provide basis for the prevention of hypertensive disorders of pregnancy.Method:A retrospective birth cohort was established for pregnant women with hypertensive disorder who were delivered in the second hospital of Jilin University,Changchun City,Jilin Province from January 2017 to September2019.The cohort consisted of 926 pregnant women.By face-to-face investigation and consulting the original medical records,their BMI before pregnancy,weight gain during pregnancy and other clinical data were collected,and they were divided into gestational hypertension group(240 cases),pre-eclampsia group(682 cases),eclampsia group(4 cases),in which pre-eclampsia group was divided into no severe features of pre-eclampsia group(155 cases)and severe pre-eclampsia group(527cases).Chi square test and multi factor logistic regression model are used to analyze the indexes involved to explore the relationship between the body mass index(BMI)before pregnancy,the weight growth during pregnancy and the progress of gestational hypertension and to explore the predictive value and obtain the ideal cutoff value for preeclampsia.To analyze the relationship among the high BMI before pregnancy(overweight or obesity),the excessive gestational weight gain,the development of hypertensive disorders of pregnancy and the occurrence of pre-eclampsia provides the basis for preventing disease occurrence.Result:1.Among the patients with hypertensive disorder,the proportion of pregnant women with high BMI(overweight/obesity)in preeclampsia group(32.99% /36.22%)is higher than which in gestational hypertension group(23.33%/14.58%).The proportion of obese pregnant women in severe preeclampsia group(45.36%)is higher than that in no severe features of preeclampsia group(9.71%),and the difference between the two groups is statistically significant(P<0.01).2.The proportion of pregnant women in preeclampsia group(57.48%)is higher than that in gestational hypertension group(26.67%).The proportion of pregnant women with severe preeclampsia(59.17%)is higher than that with no severe features of preeclampsia(52.57%),which is statistically significant(P<0.01).When the gestational weight gain exceeds the upper limit of the suitable range,the probability of preeclampsia and severe preeclampsia in the overweight and obesity groups increase significantly(P<0.01).At the same time,the proportion of patients in preeclampsia group is higher than that in gestational hypertension group(P<0.01).In the obesity group,the composition ratio of gestational weight gain in no severe features of preeclampsia group and severe preeclampsia group is the same as the general trend,but there is no statistical significance between the groups(P=0.128).3.Multivariate logistic regression analysis shows that after adjusting the age factors of pregnant women,high BMI(overweight /obesity)before pregnancy is a risk factor for the development of hypertensive disorders of pregnancy,which increases preeclampsia(OR=1.57,95%CI:1.26-1.96)and severe preeclampsia(OR=2.01,95%CI:1.53-2.65),too much gestational weight gain is a risk factor for the development of hypertensive disorders of pregnancy,which increases the risk of preeclampsia(or=2.15,95%CI:1.93-3.91),but it has no significant effect on the occurrence of severe preeclampsia.By comparing the correlation coefficient,the effect of high BMI(overweight/obesity)on the development of disease is higher than that of excessive gestational weight gain.4.The results of ROC curve analysis shows that BMI before pregnancy and gestational weight gain has certain predictive value for the occurrence of preeclampsia.The area under the BMI before pregnancy is0.804(95%CI:0.771-0.836),the sensitivity is 94.1%,and the specificity is 37.9%.The patients are divided into four groups for analysis according to the differences in the BMI before pregnancy.The area below the line of the ultra-low suite is 0.990(95%CI: 0.971-0.988).The area under the normal suite line is 0.454(95%CI: 0.351-0.556),but the results are not statistically significant(P=0.286).The area under the line of the overweight suite is 0.923(95%CI: 0.890-0.956).The area under the line of the obesity suite is 0.817(95%CI: 0.761-0.874).Except for the normal group,the area under the curve is greater than 0.7,which has good prediction value and high sensitivity,but the specificity is less than0.1.Therefore,BMI before pregnancy is of great value in predicting preeclampsia.Conclusion:1.High BMI before pregnancy(overweight/obesity)is a risk factor for disease progression of hypertensive disorders of pregnancy,which increases the risk of pre-eclampsia and severe preeclampsia.2.Under different BMI levels,gestational weight gain excess is the risk factor of preeclampsia;when BMI before pregnancy is less than 28.0,gestational weight gain excess is the risk factor of severe preeclampsia.3.When other influencing factors are consistent,both excessive BMI before pregnancy(overweight/obesity)and excessive gestational weight gain are risk factors for hypertensive disorders of pregnancy disease progression and pre-eclampsia occurrence,and the former has a significantly higher impact than the latter;At the same time,excessive BMI before pregnancy(overweight/obesity)is a risk factor for severe pre-eclampsia occurrence.4.BMI before pregnancy and the level of weight gain during pregnancy have a certain predictive value for the occurrence of pre-eclampsia,while BMI before pregnancy has a greater predictive value.