COVID‐19 infection during pregnancy and risk of early and late spontaneous miscarriages: A matched case–control population‐based study

Abstract

ObjectivesTo evaluate the effect of COVID‐19 during the first trimester on the rate of first‐ and second‐trimester miscarriages. Secondary aims include the effect on stillbirths and the correlation between symptom severity and pregnancy outcomes.MethodsA retrospective matched case–control population‐based study extracted data from electronic medical records of a nationwide database of the second largest healthcare organization that provides medical services to over 2 000 000 patients in Israel. Pregnancy outcomes in COVID‐19‐positive pregnant patients in 2020 were compared with an age‐ and gestational‐week‐matched 1:2 case–control cohort of pre‐pandemic pregnant patients that received medical care in 2019.ResultsOf 68 485 pregnant women treated in 2020, 2333 were COVID‐19‐positive during pregnancy: 215 during the first trimester, 791 during the second trimester, and 1327 during the third trimester. We compared these data with the control cohort of 4580 pre‐pandemic pregnant patients. The rate of spontaneous miscarriage was significantly higher 146/2187 (6.3%) in COVID‐19‐positive patients versus 214/4580 (4.7%), (P < 0.01, odds ratio 1.34, 95% confidence interval 1.094–1.691). Most miscarriages occurred during the first trimester in both groups, yet the rates were significantly higher in the study group (5.4% vs 3.8%, P < 0.01). There was no association between COVID‐19 severity and miscarriage risk.ConclusionCOVID‐19 diagnosis during early pregnancy increased the rate of spontaneous miscarriage in our cohort compared with an age‐ and gestational‐week‐matched pre‐pandemic control group.