Relationship of gestational weight gain with cesarean delivery risk, low birth weight and preterm labor in underweight women

Gestational weight gain (GWG) can be associated with some adverse maternal and neonatal outcomes. Relatively, in order to investigate the relationship between GWG with cesarean delivery, low birth weight and preterm birth in women with a body mass index (BMI) less than 18.5 kg per square meter, this study was accomplished.
This was a cross-sectional study. Data were collected by 103 trained midwifes from 103 hospitals, which were equipped to obstetrics and gynecology wards, in Tehran (2015). Meaningly, 234 underweight pregnant women who had singleton births were studied. GWG was categorized by institute of medicine (IOM) recommendation.
The prevalence of LBW, cesarean section and preterm birth was 5.94, 56.16 and 7.17%, respectively. The risk of cesarean delivery in women with high GWG was 2.59 times (p=0.018) than those with normal GWG. The risk of preterm birth in women with low GWG was 5.01 times (p=0.019) than those with normal GWG. Considerably, after controlling for confounder variables, no significant association was observed between GWG and low birth weight in underweight women.
In underweight women (BMI less than 18.5 kg per square meter), the risk of preterm birth, and the risk of cesarean delivery, respectively, was increased with GWG less and more than the recommended amounts by IOM