Effect of maternal body mass index on pregnancy outcome and newborn weight

Background: Maternal obesity has been associated with adverse pregnancy outcomes, such as pre-eclampsia, eclampsia, pre- and post-term delivery, induction of labor, macrosomia, increased rate of caesarean section, and post-partum hemorrhage. The objective of this study was to determine the effect of maternal Body Mass Index (BMI) on pregnancy outcomes. Methods. 1000 pregnant women were enrolled in the study. In order to explore the relationship between maternal first trimester Body Mass Index and pregnancy outcomes, participants were categorized into five groups based on their first trimester Body Mass Index. The data were analyzed using Pearson Chi-square tests in SPSS 18. Differences were considered significant if p < 0.05. Results: Women with an above-normal Body Mass Index had a higher incidence of pre-eclampsia, induction of labor, caesarean section, pre-term labor, and macrosomia than women with a normal Body Mass Index (controls). There was no significant difference in the incidence of post-term delivery between the control group and other groups. Conclusion: Increased BMI increases the incidence of induction of labor, caesarean section, pre-term labor and macrosomia. The BMI of women in the first trimester of pregnancy is associated with the risk of adverse pregnancy outcome. © 2012 Yazdani et al; licensee BioMed Central Ltd.