Association of maternal body mass index with adverse maternal and prenatal outcomes

Introduction: The present study aimed to determine the association between abnormal maternal body mass index and adverse maternal/prenatal outcomes. Materials and Methods: In this descriptive-correlation study 8270 pregnant women referred to rural and urban health centers in the Ardabil district (from Mar 2009 to Dec 2010) were studied. Data were collected from prenatal healthcare records using a self designed questionnaire. Women with twin pregnancy, less than 18 and above 35 of age, and women with systemic or chronic disease were excluded from the study. The variables examined in this study include, demographic information (e.g. age, social and economic status and literacy), present pregnancy information (e.g. parity, hemoglobin level, gestational diabetes, preeclampsia) and prenatal information (e.g. preterm delivery, low birth weight and congenital malformation). Data were analyzed through Kruscal wallis, chi-square and logistic regression tests using SPSS-16. Results: 8.2, 25 and 15.4% pregnant women were underweight, overweight and obese, respectively. Obese women were at increased risk for macrosomia (OR=1.820, CI: 1.345-2.447, p=0.001), unwanted pregnancy (OR= 1.436, CI: 1.198-1.720, p=0.001), pregnancy induced hypertension (OR= 1.633, CI: 1.072-2.486, p=0.022), preeclampsia (OR= 4.666, CI: 2.353-9.2550, p=0.001) and still birth (OR= 2.602, CI: 1.306-5.184, p=0.007). However, the risk of low birth weight delivery in underweight women were 1.6 times higher than the normal cases (OR= 1.674, CI: 0962-2.912, p=0.068). Conclusion: Considering the high prevalence of abnormal maternal body mass index and its associated adverse maternal and prenatal outcomes; consultation before pregnancy is recommended in order to achieve normal body mass index and reduce the relevant complications.