Incidence, characteristics, and maternal outcomes of pregnancy with uterine prolapse

Background: Gravid uterine prolapse refers to abnormal descent of the uterus during pregnancy. It is a rare pregnancy complication and its clinical characteristics and obstetrical outcomes are not well understood.

Objective: This study aimed to assess the national-level incidence, characteristics, and maternal outcomes of pregnancies complicated by gravid uterine prolapse.

Study design: This retrospective cohort study queried the Healthcare Cost and Utilization Project's National Inpatient Sample. The study population was 14,647,670 deliveries from January 2016 to December 2019. The exposure assignment was the diagnosis of uterine prolapse. The coprimary outcome measures were incidence rate, clinical and pregnancy characteristics, and delivery outcomes of patients with gravid uterine prolapse. The inverse probability of treatment weighting cohort was created to mitigate the difference in prepregnancy confounding factors, followed by adjusting for pregnancy and delivery factors.

Results: The incidence of gravid uterine prolapse was 1 in 4209 deliveries (23.8 per 100,000). In a multivariable analysis, older age (≥40 years; adjusted odds ratio, 3.21; 95% confidence interval, 2.70-3.81); age from 35 to 39 years (adjusted odds ratio, 2.66; 95% confidence interval, 2.37-2.99); Black (adjusted odds ratio, 1.48; 95% confidence interval, 1.34-1.63), Asian (adjusted odds ratio, 1.45; 95% confidence interval, 1.28-1.64), and Native American (adjusted odds ratio, 2.17; 95% confidence interval, 1.63-2.88) race/ethnicity; tobacco use (adjusted odds ratio, 1.19; 95% confidence interval, 1.03-1.37); grand multiparity (adjusted odds ratio, 1.78; 95% confidence interval, 1.24-2.55); and history of pregnancy losses (adjusted odds ratio, 2.20; 95% confidence interval, 1.48-3.26) were the patient characteristics associated with increased risk of gravid uterine prolapse. Current pregnancy characteristics associated with gravid uterine prolapse included cervical insufficiency (adjusted odds ratio, 3.25; 95% confidence interval, 1.94-5.45), preterm labor (adjusted odds ratio, 1.53; 95% confidence interval, 1.18-1.97), preterm premature rupture of membranes (adjusted odds ratio, 1.40; 95% confidence interval, 1.01-1.94), and chorioamnionitis (adjusted odds ratio, 1.64; 95% confidence interval, 1.18-2.28). Delivery characteristics associated with gravid uterine prolapse included early-preterm delivery at <34 weeks' gestation (69.1 vs 32.0 per 1000; adjusted odds ratio, 1.86; 95% confidence interval, 1.34-2.59) and precipitate labor (35.2 vs 20.1; adjusted odds ratio, 1.73; 95% confidence interval, 1.22-2.44). Moreover, risks of postpartum hemorrhage (112.1 vs 44.4 per 1000; adjusted odds ratio, 2.70; 95% confidence interval, 2.20-3.32), uterine atony (32.0 vs 15.7; adjusted odds ratio, 2.10; 95% confidence interval, 1.46-3.03), uterine inversion (9.6 vs 0.3; adjusted odds ratio, 31.97; 95% confidence interval, 16.60-61.58), shock (3.2 vs 0.7; adjusted odds ratio, 4.18; 95% confidence interval, 1.41-12.40), blood product transfusion (22.4 vs 11.1; adjusted odds ratio, 2.06; 95% confidence interval, 1.34-3.18), and hysterectomy (7.5 vs 2.3; adjusted odds ratio, 3.02; 95% confidence interval, 1.40-6.51) were increased in the gravid uterine prolapse group compared with the nonprolapse group. Conversely, patients with gravid uterine prolapse were less likely to deliver via cesarean delivery compared with those without gravid uterine prolapse (200.6 vs 322.8 per 1000; adjusted odds ratio, 0.51; 95% confidence interval, 0.44-0.61).

Conclusion: This nationwide analysis suggests that pregnancy with gravid uterine prolapse is uncommon but associated with several high-risk pregnancy characteristics and adverse delivery outcomes.