Impact of COVID-19 on Pregnancy Outcomes: A Propensity Score Matched Study

ABSTRACT

INTRODUCTION: Available data on the association between COVID- 19 and adverse pregnancy outcomes is limited by ascertainment bias. Our objective was to assess the impact of COVID-19 on pregnancy outcomes in a propensity score matching (PSM) study. This allows for balancing of observed baseline covariates and decreases the effect of confounding factors. METHODS: We conducted a retrospective, multicenter, case-control study to understand the association between COVID-19 and pregnancy outcomes. We reviewed all consecutive charts of adult females aged 18-45 years with SARS-CoV-2 infection betweenMarch 1, 2020, and August 31, 2020. Cases were patients diagnosed with COVID-19 during pregnancy (COVID+), whereas controls were pregnant patients who tested negative for COVID-19 (COVID-). We excluded cases with multiple gestation or incomplete data. PSM was performed using age, race/ethnicity, body mass index, and past medical history. The primary outcome was a compound score of pregnancy complications (pregnancy loss, neonatal demise, fetal growth restriction, hypertensive disorders of pregnancy, preterm premature rupture of membranes, preterm delivery, and placental abruption). Analyses were performed with SAS software. RESULTS: A total of 2,474 patients were identified, of which 2,374 were COVID- and 100 COVID+. There was a trend toward higher rate of adverse pregnancy outcomes in the COVID+ group (48 [48%] versus 917 [38.7%], P=.06). The results remained unchanged after optimal oneto- four PSM was applied (48 [48%] versus 151 [37.8%], P=.06). CONCLUSION: COVID-19 in pregnancy appears to be associated with an increased risk for adverse pregnancy outcomes. Although our study had a trend toward statistical significance, further research with a large sample size is required.