Maternal and perinatal outcomes in pregnant women with BMI >50: An international collaborative study.

OBJECTIVE

To examine the association between maternal BMI>50kg/m2 during pregnancy and maternal and perinatal outcomes.

MATERIALS AND

METHODS

An international cohort study was conducted using data from separate national studies in the UK and Australia. Outcomes of pregnant women with BMI>50 were compared to those of pregnant women with BMI<50. Multivariable logistic regression estimated the association between BMI>50 and perinatal and maternal outcomes.

RESULTS

932 pregnant women with BMI>50 were compared with 1232 pregnant women with BMI<50. Pregnant women with BMI>50 were slightly older, more likely to be multiparous, and have pre-existing comorbidities. There were no maternal deaths, however, extremely obese women had a nine-fold increase in the odds of thrombotic events compared to those with a BMI<50 (uOR: 9.39 (95%CI:1.15-76.43)). After adjustment, a BMI>50 during pregnancy had significantly raised odds of preeclampsia/eclampsia (aOR:4.88(95%CI: 3.11-7.65)), caesarean delivery (aOR: 2.77 (95%CI: 2.31-3.32)), induction of labour (aOR: 2.45(95% CI:2.00-2.99)) post caesarean wound infection (aOR:7.25(95%CI: 3.28-16.07)), macrosomia (aOR: 8.05(95%CI: 4.70-13.78)) compared a BMI<50. Twelve of the infants born to women in the extremely obese cohort died in the early neonatal period or were stillborn.

CONCLUSIONS

Pregnant women with BMI>50 have a high risk of inferior maternal and perinatal outcomes.