Abstract
Objective
This study aimed to evaluate the frequency of adverse maternal and neonatal outcomes
associated with maternal obesity in a Hispanic population. We hypothesized that obesity
confers a dose-dependent risk associated with these outcomes.
Study Design
This was a retrospective cohort study of singleton pregnancies delivered between 24
and 42 weeks gestation at an urban county hospital between 2013 and 2021. Body mass
index (BMI) at the first prenatal visit was used as a proxy for prepregnancy weight.
Patients were excluded if their first-trimester BMI was not available. Trends in adverse
outcomes across increasing obesity classes were assessed.
Results
During the study period, 58,497 patients delivered a singleton infant, of which 12,365
(21.1%), 5,429 (9.3%), and 3,482 (6.0%) were in class I, II, and III obesity, respectively.
Compared with nonobese patients, obese patients were more likely to be younger and
nulliparous with a higher incidence of hypertension and pregestational diabetes. Higher
BMI was associated with a significant dose-dependent increase in cesarean delivery
(27% for nonobese, 34% for class I, 39% for class II, and 46% for class III obesity);
severe preeclampsia (8% in nonobese and 19% for class III obesity); and gestational
diabetes (5% in nonobese and 15% in class III obesity). There were significant trends
in increasing morbidity for infants born to patients with correspondingly higher obesity
classes. Some of these adverse outcomes included respiratory distress syndrome, neonatal
intensive care unit admission, fetal anomalies, and sepsis (all p < 0.001).
Conclusion
Increasing body mass index is associated with a significant dose-dependent increase
in multiple adverse perinatal outcomes in a Hispanic population. Associated adverse
maternal outcomes include severe preeclampsia, gestational diabetes, and cesarean
delivery. Infants born to patients with correspondingly higher BMI class have significantly
increased associated morbidity. Often, only higher BMI classes are significantly associated
with these adverse outcomes.
Key Points
-
As BMI increases, pregnant patients are more likely to experience adverse maternal
and neonatal outcomes.
-
Many adverse pregnancy outcomes are associated only with a BMI greater than 40 kg/m2.
-
Obesity is associated with cesarean delivery, likely due to an increase in labor dystocia.
Keywords
obesity - maternal morbidity - neonatal outcomes - body mass index - hypoxic-ischemic
encephalopathy - cesarean delivery
