Abstract

A severe third wave of COVID-19 disease affected Ireland in the first three months of 2021. In this wave, one second-trimester miscarriage and six stillbirths were observed in the Irish population due to placental involvement in the infection, a condition called “SARS-CoV-2 Placentitis”. This observation was at odds with the country's previous experience with COVID-19 disease in pregnancy. Information was available for review in six of these pregnancies. Impairment of the babies’ growth was not identified which suggested that the placental disease progressed rapidly and proved fatal before growth could be affected. The identification of the SARS-CoV-2 alpha variant in all six cases suggested that the emergence of the variant was associated with an increased risk of fetal death due to SARS-CoV-2 placentitis when compared with the original virus. Low maternal platelets, seen in three cases, may have potential as a clinical marker of placental involvement in COVID-19. Three of the six women had been assessed for reduced fetal movements in hospital some days before the fetal deaths actually occurred; this could suggest that there may be a window for intervention in some cases.