Trends in adverse pregnancy outcomes among women with systemic sclerosis in the United States

Objectives: We sought to examine temporal trends in adverse pregnancy outcomes among SSc pregnancies in a large nationwide sample.Methods: We used the National Inpatient Sample (NIS) database from 2000 - 2017 to derive national estimates of delivery-associated hospitalizations in the United States among patients with SSc. Each SSc delivery was matched to 100 non-SSc deliveries by age, delivery year, and race. We evaluated adverse pregnancy outcomes (APOs) including maternal and fetal death, cesarean delivery, hospital length of stay, preterm delivery, intrauterine growth restriction, and hypertensive disorders of pregnancy. We used multivariable regression models with an interaction term between SSc and year and adjusting for race, advanced maternal age, diabetes mellitus, and pre-existing hypertension to evaluate temporal trends in APOs among SSc and non-SSc deliveries.Results: From 2000 to 2017, there were 3740 delivery-associated hospitalizations for women with SSc. SSc was associated with an increased risk of all APOs compared to non-SSc deliveries. Fetal death declined in SSc de-liveries from 49.0 per 1000 delivery-related admissions in 2000 - 2005 to 16.2 per 1000 in 2012 - 2017. There was a significant difference in trends for fetal death between SSc and non-SSc deliveries (p = 0.043), but the trends for other APOs did not differ between the two groups.Conclusions: In this large nationwide sample, the risk of fetal death among women with SSc markedly improved over the past 18 years. The risk for other APOs remained high in SSc deliveries compared to non-SSc deliveries, and further studies are needed to determine what strategies can improve these outcomes.