Abstract
Objective
Prepregnancy obesity (PPO) and excessive gestational weight gain (eGWG) during pregnancy,
both are associated with adverse neonatal outcomes. The objective of this study was
to compare the independent associations of PPO and eGWG with adverse neonatal outcomes.
Study Design
This was a retrospective cohort study of singleton, live births in the United States
in 2018 using National Vital Statistics System data. These were divided into four
groups: 1) normal prepregnancy BMI and normal GWG, 2) normal prepregnancy BMI and
eGWG, 3) prepregnancy BMI >30 kg/m2 (PPO) and normal GWG and 4) PPO and eGWG. The adverse neonatal outcomes, including
preterm delivery, large for gestational age (LGA) infants, assisted neonatal ventilation,
low 5-minute Apgar scores, neonatal intensive care unit (NICU) admissions, and surfactant
use were studied. These outcomes were compared among groups using ANOVA and multivariable
analyses.
Results
Of the 1,477,062 births included, 21.8, 41.6, 10.4, and 26.3% were in groups 1 to
4, respectively. With group 1 as the reference group after correcting for significant
factors, groups 2 to 4 had a higher risk (adjusted odds ratio with 95% confidence
interval), for preterm delivery of <37 weeks 1.17 (1.14–1.20), 1.05 (1.02–1.09), and
1.14 (1.11–1.18) and for LGA infants 2.38 (2.31–2.44), 2.37 (2.29–2.45), and 3.91
(3.80–4.02) in groups 2 to 4, respectively. Further, patients with PPO with and without
eGWG also had increased risk of immediate assisted neonatal ventilation 1.07 (1.02–1.12)
and 1.16 (1.12–1.22), for 5-minute Apgar score <3 1.40 (1.19–1.65) and 1.38 (1.20–1.58),
and for NICU admission in 1.04, (1.01–1.08) and 1.12 (1.09–1.15) for groups 3 and
4, respectively.
Conclusion
Both PPO and eGWG were independently associated with preterm delivery and LGA infants.
PPO with or without excessive GWG was also associated with low Apgar scores, more
NICU admissions, and a higher need for immediate ventilatory support. This data supports
the importance of prepregnancy weight loss to prevent or decrease adverse neonatal
outcomes.
Key Points
Maternal obesity is associated with adverse neonatal outcomes.
Maternal obesity is due to PPO or eGWG.
To study the contribution of adverse neonatal outcomes by PPO as distinct from excessive
GWG.
To study the increasing maternal prepregnancy BMI to the incidence of adverse neonatal
outcomes.
Keywords prepregnancy obesity - gestational weight gain - prematurity - neonatal outcomes
