Association between congenital uterine anomalies and placenta accreta spectrum.

OBJECTIVE

To evaluate the association between congenital uterine anomalies (CUAs) and placenta accreta spectrum (PAS) in a large, nationally representative sample.

DESIGN

Cross-sectional, observational study using the US National Inpatient Sample from 2017 to 2021. Logistic regression models were constructed to evaluate associations between the exposure and the outcome. Predetermined confounding variables included age, history of a cesarean delivery, and placenta previa. A sensitivity analysis was performed including only patients with a code for placenta accreta spectrum who also underwent hysterectomy. Data were weighted according to National Inpatient Sample complex sampling weights to account for year-to-year variation and to extrapolate estimates to the US population.

SUBJECTS

Pregnant patients at ≥20 weeks' gestation with International Classification of Disease codes for congenital uterine anomalies or PAS.

EXPOSURE

Code for at least 1 of the CUAs.

MAIN OUTCOME MEASURES

Code for at least 1 of the types of PAS during delivery hospitalization.

RESULTS

The study cohort included 17,594,765 (or 3,518,955 unweighted) individuals. CUAs were present in 78,809 (0.45%, 15,259 unweighted) individuals. PAS was more frequent in patients with CUA than in those without (0.42% vs. 0.12%), with a weighted odds ratio (OR) of 3.36 (95% confidence interval [CI], 2.62-4.32; unweighted OR, 3.37 [95% CI, 2.63-4.31]). When controlling for age, prior cesarean, and placenta previa, the odds of having PAS was higher in those with a CUA than in those without (weighted adjusted OR [aOR], 2.46 [95% CI, 1.87-3.17]; unweighted aOR, 2.44 [95% CI, 1.88-3.16]). In the sensitivity analysis including only individuals with PAS who underwent a hysterectomy, CUA continued to be associated with PAS (weighted aOR, 2.26 [95% CI, 1.52-3.36]; unweighted aOR, 2.26 [95% CI, 1.55-3.31]).

CONCLUSION

In this population-based study, CUAs were associated with an increased odds of PAS. Patients with CUA should have careful screening for PAS at the time of routine obstetric ultrasound.