Pregnancy outcomes in super-obese women – an even bigger problem? A prospective cohort study

Abstract

Objective. To investigate whether differences exist in adverse pregnancy outcomes between morbidly obese (body mass index (BMI, kg/m²) 40 - 49.9) and super-obese women (BMI ≥50).

Methods: A prospective cohort study was undertaken at Tygerberg Hospital, a referral centre in the Western Cape Province of South Africa, of morbidly obese and super-obese pregnant women recruited from the antenatal clinic. Data were collected from the files 6 weeks after delivery. Primary outcomes included hypertension, diabetes mellitus and fetal macrosomia. Secondary outcomes included baseline characteristics, previous complications, antenatal and peripartum complications, and short-term neonatal outcomes.

Results. Sixty-six morbidly obese and 46 super-obese women were enrolled. Super-obese women experienced significantly higher incidences of pre-eclampsia (24% v. 9%; p=0.03) and interuterine growth restriction (13% v. 2%; p=0.02) than morbidly obese women, and both groups had a high incidence of gestational diabetes (24% v. 24%; non-significant (NS)). Both super-obese and morbidly obese women experienced high rates of caesarean section (54% v. 41%; NS). In super-obese women these procedures lasted longer (50 v. 41 minutes; p<0.01) and there were more surgical complications (36% v. 7%; p=0.01). Prolonged admission (>3 days) after delivery was also more common in super-obese women (65% v. 42%; p=0.03).

Conclusion. Super-obese women encounter more major pregnancy complications (especially hypertensive, pre-eclamptic and surgical) than morbidly obese women, emphasising the fact that these women should be managed at institutions with sufficient expertise.