Higher prepregnancy body mass index is a risk factor for developing preeclampsia in Maya-Mestizo women: a cohort study

Aim: Preeclampsia and obesity are two closely related syndromes. The high maternal prepregnancy body mass index (BMI) is a risk factor for present preeclampsia, independently of the ethnic background of the studied population. The aim of this study was to analyse in a prospective cohort study the relation between prepregnancy BMI and development of preeclampsia in Maya-Mestizo women. Design: This is a prospective cohort study of 642 pregnant women that were included in the first trimester of the pregnancy (gestational age ≤12 weeks at the first antenatal visit) and all of them were of Maya-Mestizo ethnic origin from the state of Yucatán, México. We assessed the potential risk factors for preeclampsia and documented the prepregnancy BMI (kg/m²) that was based on measured height and maternal self-report of prepregnancy weight at the initial visit. Besides, in the antenatal visit we documented if the pregnant women developed preeclampsia. Results: Of the 642 pregnant Maya-Mestizo women, 49 developed preeclampsia, with an incidence of 7.6% (44.9% had severe and 55% mild). The prepregnancy BMI was higher in women with developed preeclampsia than in those with normal pregnancies. Women with overweight or obesity in comparison with normal weight presented a RR = 2.82 (95% CI: 1.32–6.03; P = 0.008) and RR= 4.22 (95% CI: 2.07–8.61; P = 0.001), respectively. Conclusions: Our findings expand the previous studies to show that the higher prepregnancy BMI is a strong, independent risk factor for preeclampsia.