COVID-19 during pregnancy should we really worry from vertical transmission or rather from fetal hypoxia and placental insufficiency? A systematic review

AbdelMassih, Antoine; Fouda, Raghda; Essam, Rana; Negm, Alhussein; Khalil, Dalia; Habib, Dalia; Afdal, George; Ismail, Habiba-Allah; Aly, Hadeer; Genedy, Ibrahim; El Qadi, Layla; Makki, Leena; Shulqamy, Maha; Hanafy, Maram; AbdelMassih, Marian; Ibrahim, Marina; Ebaid, Mohamed; Ibrahim, Monica; El-Husseiny, Nadine; Ashraf, Nirvana; Shebl, Noura; Menshawey, Rahma; Darwish, Rama; ElShahawi, Rana; Ramadan, Rana; Albala, Sadra; Imran, Salwa; Ahmed, Sama; Khaldi, Samer; Abohashish, Sara; Paulo, Stavro; Omar, Yasmin; Tadros, Mourad Alfy

BACKGROUND: COVID-19 is the largest outbreak to strike humanity. The wide scale of fatalities and morbidities lead to a concurrent pandemic of uncertainty in scientific evidence. Conflicting evidences are released on daily basis about the neonatal outcomes of COVID-19-positive mothers. The aim of this study was to use the relevant case reports and series to determine the percentage of newborns who test positive for COVID-19 who are born to COVID-19-positive mothers. Secondary outcomes included examining laboratory abnormalities among COVID-19-positive neonates, and any depicted placental abnormalities in COVID-19-positive mothers. For this purpose, systematic review was performed on all studies reporting primary data on fetus-mother pairs with COVID-19. Data bases were searched for studies that met our inclusion and exclusion criteria. RESULTS: Final screening revealed 67 studies, from which the primary data of 1787 COVID-19 mothers were identified and had their pregnancy outcome analyzed. Only 2.8% of infants born to COVID-19-positive mothers tested positive, and this finding is identical to percentages reported in former Coronaviridae outbreaks, whereas 20% manifested with intrauterine hypoxia alongside placental abnormalities suggestive of heavy placental vaso-occlusive involvement. CONCLUSIONS: These findings suggest that while vertical transmission is unlikely, there appears to be an underlying risk of placental insufficiency due to the prothrombotic tendency observed in COVID-19 infection. Guidelines for proper prophylactic anticoagulation in COVID-positive mothers need to be established.