Effect of body mass index on pregnancy outcomes in nulliparous women delivering singleton babies: observational study

To find out the effect of increasing body mass index (BMI) on pregnancy outcomes in nulliparous women delivering singleton babies.

This was a hospital-based observation study, based on 300 nulliparous women delivering singleton babies in June 2009-Sept. 2010. Women were categorized into three groups. Underweight (BMI < 20 kg/m(2)), normal (BMI 20-24.9 kg/m(2)), overweight (BMI 25-29.9 kg/m(2)), and obese (BMI > 30 kg/m(2)) obstetric and perinatal outcomes were compared by univariate and multivariate analysis.

Maximum patients who underwent LSCS were having BMI > 30 kg/m(2) [OR 9.558 (95 % CI 5.82-17.27)]. As compared to women of normal BMI (20-24.9 kg/m(2)), morbidly obese women faced the higher risk of PIH [OR 8.045 (95 % CI 3.875-16.781)]. Obese women were more likely to have post partum hemorrhage [OR 5.11 (95 % CI 1.76-14.79)] compared with women of normal BMI. Birth weight <2,500 g was more common in women with BMI < 25 kg/m(2) (21.21 %), while highest incidence of birth weight >4,000 g (14.29 %) is seen in women of the obese group.

Increasing BMI is associated with increased incidence of cesarean delivery, PIH, post partum hemorrhage, and macrosomic babies.