Impact of Body Mass Index and Height on Hypertensive Disorders in Pregnancy

Abstract

Introduction: Hypertension is common cause of morbidity and mortality in pregnant females. Hence, prevention and management of preeclampsia is necessity. Maternal Body Mass Index (BMI) and preeclampsia are inter-related. South Asian females are prone to obesity. Aim: To find relation among maternal BMI, height and gestational hypertension or preeclampsia, and to assess the severity of hypertensive disorders during pregnancy and maternal and foetal outcomes Materials and Methods: This prospective observational cohort study was conducted in Department of Obstetrics and Gynaecology in Vardhman Mahavir Medical College and Safdarjung Hospital (tertiary care hospital), Delhi, India, from September 2013 to December 2014. The study involved pregnant women with gestational age less than 14 weeks. After registration, body weight and height of all the subjects were measured during the first prenatal visit and recorded. Blood pressure was measured at every antenatal visit. The subjects were followed-up once monthly till 32 weeks, every 15 days till 36 weeks and weekly thereafter till delivery. To compare the baseline parameters between the two groups of patients, Chi-square test was used for categorical variables. A two-sided p-value <0.05 was statistically significant. To find out the correlation between BMI and height with pregnancy Pearson correlation coefficient test was used. Results: Total 375 consecutive pregnant women, 44 were lost to follow-up, hence, 331 were followed-up. Obese group constituted 21.8%, majority (38.1%) had normal BMI. Overweight /obese women suffered hypertensive complications more than normal and underweight women (p-value=0.001). Short height (<150 cm) pregnant females were more prone to develop hypertensive complications (p-value=0.03). The BMI (as continuous variable) was positively correlated with pregnancy induced hypertension (r=0.351; p-value <0.0001). As BMI increases, the PIH severity increases (p-value <0.0001). However, height (as continuous variable) of the patients was negatively correlated with PIH severity (r=-0.170; p-value=0.002) and as the height of patient decreases, risk of PIH severity increases. Conclusion: Short stature and high BMI pregnant females are more prone to develop hypertensive disorders and preeclampsia. Preconception prior counselling regarding weight optimisation is must.