Maternal transmission of SARS-COV-2 to the neonate, and possible routes for such transmission: A systematic review and critical analysis

Background: Early reports of COVID-19 in pregnancy described management by caesarean, strict isolation of the neonate and formula feeding, is this practise justified?. Objective: To estimate the risk of the neonate becoming infected with SARS-COV-2 by mode of delivery, type of infant feeding and mother-infant interaction. Search Strategy: Two biomedical databases were searched between September 2019 - June 2020. Selection Criteria: Case reports or case series of pregnant women with confirmed COVID-19, where neonatal outcomes were reported. Data Collection and Analysis: Data was extracted on mode of delivery, infant infection status, infant feeding and mother-infant interaction. For reported infant infection a critical analysis was performed to evaluate the likelihood of vertical transmission. Main Results: We included 49 studies which included 666 neonates and 655 women where information was provided on the mode of delivery and the infant’s infection status. 28/666 (4%) neonates had confirmed COVID-19 infection postnatally. Of the 291 women who delivered vaginally, 8/292 (2.7%) neonates were positive. Of the 364 women who had a Caesarean birth, 20/374 (5.3%) neonates were positive. Of the 28 neonates with confirmed COVID-19 infection, 7 were breast fed, 3 formula fed, 1 was given expressed breast milk and in 17 neonates the method of infant feeding was not reported. Conclusions: Neonatal COVID-19 infection is uncommon, uncommonly symptomatic, and the rate of infection is no greater when the baby is born vaginally, breastfed or allowed contact with the mother.