National-level assessment of gestational carrier pregnancies in the United States.

Purpose: To assess national trends, characteristics, and delivery outcomes associated with gestational carriers (GC) pregnancies.

Methods: This cross-sectional study queried the Healthcare Cost and Utilization Project's National Inpatient Sample. The study population was 14,312,619 deliveries between 2017 and 2020. Obstetric characteristics and outcomes associated with GC pregnancies were assessed with inverse probability of treatment weighting propensity score.

Results: There were 1965 GCs (13.7 per 100,000) included for national estimates. The prevalence rate of GC pregnancies increased by 55.0% over a 4-year period from 11.8 to 18.2 per 100,000 deliveries (P-trend < .001). In the weighted model, GCs were more likely to have a multiple gestation pregnancy (14.7% vs 1.8%, adjusted odds ratio [aOR] 7.83, 95% confidence interval [CI] 6.54-9.38, P < .001), placental abruption (3.5% vs 1.1%, aOR 2.98, 95%CI 2.12-4.19), and low-lying placenta (1.6% vs 0.2%, aOR 5.14, 95%CI 3.10-8.52). Among singleton delivery, odds of late-preterm (10.8% vs 6.4%, aOR 1.79, 95%CI 1.44-2.23) and periviable (1.1% vs 0.4%, aOR 2.54, 95%CI 1.32-4.89) deliveries and postpartum hemorrhage (12.2% vs 4.1%, aOR 3.27, 95%CI 2.67-4.00) were increased for GC compared to non-GCs whereas odds of cesarean delivery (23.6% vs 31.6%, aOR 0.59, 95%CI 0.51-0.69) were decreased. These associations were less robust in multi-fetal gestations.

Conclusion: The results of the current nationwide assessment suggest that GC pregnancies are rare but gradually increasing in the United States. This study shows that GC pregnancies have usually favorable pre-pregnancy patient characteristics compared to non-GC pregnancies, with mixed obstetric outcomes including increased odds of preterm delivery, placental abnormalities, and postpartum hemorrhage and decreased odds of cesarean delivery in singleton pregnancies.