Pregnancy, delivery, and neonatal outcomes among women living with Down syndrome: a matched cohort study, utilizing a population database.

Purpose: We utilized a population database to address the paucity of data around pregnancy outcomes in women with Down syndrome (DS).

Methods: We conducted a retrospective study using the Health Care Cost and Utilization Project-Nationwide Inpatient Sample Database over 11 years, from 2004 to 2014. A delivery cohort was created using ICD-9 codes. ICD-9 code 758.0 was used to extract the cases of maternal DS. Pregnant women with DS (study group) were matched based on age, race, income, and health insurance type to women without DS (control) at a ratio of 1:20.

Results: There were a total of 9,096,788 deliveries during the study period. Of those, 184 pregnant women were found to have DS. The matched control group was 3680. After matching, most of the pregnancy and delivery outcomes, such as pregnancy-induced hypertension, gestational diabetes, preterm premature rupture of membrane, chorioamnionitis, cesarean section, operative vaginal delivery, or blood transfusion were similar between participants with and without DS. However, patients with DS were at increased risk of giving birth prematurely (aOR 3.09, 95% CI 2.06-4.62), and having adverse neonatal outcomes such as small for gestational age (aOR 2.70, 95% CI 1.54-4.73), intrauterine fetal demise (aOR 22.45, 95% CI 12.02-41.93), congenital anomalies (aOR 7.92, 95% CI 4.11-15.24), and fetal chromosomal abnormalities.

Conclusion: Neonates to mothers with DS are at increased risk of prematurity and other neonatal adverse outcomes. Hence, counseling patients with DS about these risks and increased antenatal surveillance is advised.