Histopathologic evaluation of placentas after diagnosis of maternal severe acute respiratory syndrome coronavirus 2 infection.

Background The impact of maternal severe acute respiratory syndrome coronavirus 2 infection on placental histopathology is not well known. Objective To determine if any significant placental histopathologic changes occur after the diagnosis of severe acute respiratory syndrome coronavirus 2 infection during pregnancy and whether these changes are correlated with the presence or absence of symptoms associated with the infection. Study Design A retrospective cohort study of women diagnosed as having severe acute respiratory syndrome coronavirus 2 infection who delivered at a single center from April 9, 2020 to April 27, 2020, and had placental specimens reviewed by the Department of Pathology. Women with singleton gestations and laboratory-confirmed severe acute respiratory syndrome coronavirus 2 infection were eligible for inclusion. Historical controls selected from a cohort of women who delivered 6 months before the study period were matched in a 1:1 fashion by weeks of gestation at delivery. Histopathologic characteristics were evaluated in each placenta, and the incidence of these findings was compared between placentas of those who received a diagnosis of maternal severe acute respiratory syndrome coronavirus 2 infection and historical controls, and between placentas from patients with or without typical symptoms related to the infection. Statistical analyses included the use of Wilcoxon rank-sum test and Fisher’s exact test for the comparison of categorical and continuous variables. Statistical significance was defined as a P value of Results A total of 50 placentas after the diagnosis of maternal severe acute respiratory syndrome coronavirus 2 infection and 50 historical controls were analyzed. Among the placentas from patients diagnosed with severe acute respiratory syndrome coronavirus 2 infection, 3 (6%) were preterm (33 3/7, 34 6/7, and 36 6/7 weeks of gestation), 16 (32%) were from patients with typical symptoms related to the infection, and 34 (68%) were from patients without typical symptoms related to the infection. All patients had received a diagnosis of severe acute respiratory syndrome coronavirus 2 infection in the third trimester. Decidual vasculopathy was not visualized in any of the placentas from patients diagnosed as having severe acute respiratory syndrome coronavirus 2 infection. There was no statistically significant difference in placental histopathologic characteristics between the groups. Severe acute respiratory syndrome coronavirus 2 test results for all neonates at 24 hours of life were negative. Conclusion Based on the results of this study, there are no significant placental histopathologic changes that occur after the diagnosis of severe acute respiratory syndrome coronavirus 2 infection in women during the third trimester of pregnancy compared with a gestational age–matched historical control group. Similar incidences of histopathologic findings were also discovered when comparing placentas from patients with severe acute respiratory syndrome coronavirus 2 infection with or without the presence of symptoms typically related to the infection.