Pre-pregnancy body mass index and pregnancy outcomes

Int J Gynaecol Obstet. 2006 Dec;95(3):242-7. doi: 10.1016/j.ijgo.2006.06.021. Epub 2006 Sep 27.


Objective: To determine the effect of maternal pre-pregnancy BMI on pregnancy outcomes.

Methods: Pregnancy cohort recruited pregnancies between 16 and 18 weeks. BMI evaluated underweight, BMI<18.5, normal, BMI 18.5-25, overweight BMI 25-30, and obese BMI>30 women.

Results: Pre-pregnancy BMI classified 331 women as underweight (11.7%), 1982 normal (69.9%), 326 overweight (11.5%), and 188 as obese (6.6%). Obese women were more likely to develop gestational diabetes (p<0.001), hypertension (p<0.001), preeclampsia (p<0.001), need labor induction (p<0.001), cesarean delivery for fetal distress (p<0.001), postpartum hemorrhage (p=0.003), need neonatal resuscitation (p=0.001) and deliver hypoglycemic infants (p=0.007). Being underweight is correlated with fetal growth restriction (p=0.001).

Conclusion: Pre-pregnancy obesity is a risk factor for gestational diabetes, preeclampsia, labor induction, cesarean for fetal distress, postpartum hemorrhage and neonatal hypoglycemic and need for resuscitation. Being underweight is risk factor for fetal growth restriction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Mass Index*
  • Cohort Studies
  • Female
  • Humans
  • Infant, Newborn
  • Obesity / complications*
  • Obstetric Labor Complications*
  • Overweight
  • Pregnancy
  • Pregnancy Complications*
  • Pregnancy Outcome*
  • Risk Factors
  • Thinness / complications*