SARS-CoV-2 positivity in offspring and timing of mother-to-child transmission: living systematic review and meta-analysis

A detailed review of the evidence around rates of SARS-CoV-2 positivity in babies born to mothers with COVID-19 infection showed that these rates were low, and were more likely in women with severe disease, and confirmed that vertical transmission was possible, although rare.


Keelin O'Donoghue

Journal Name
British Medical Journal (BMJ)
Journal Article
Full Citation

Allotey J, Kew T, Fernández-García S, Gaetano-Gil A, Yap M, Sheikh J, Littmoden M, Akande O, Khalil H, Kumaran M, Barry K, Attarde S, Sambamoorthi D, Ramkumar A, Lawson H, Manning M, Maddock S, Gupta A, Hebbar M, Khashaba A, Ansari K, Banjoko A, Walker K, O’Donoghue K, van Wely M, van Leeuwen E, Kostova E, Kunst H, Khalil A, Brizuela V, Kara E, Rahn Kim C, Thorson A, Oladapo OT, Zamora J, Bonet M, Mofenson L, Thangaratinam S, on behalf of the PregCOV-19 Living Systematic Review Consortium. SARS-CoV-2 positivity in offspring and timing of mother-to-child transmission: living systematic review and meta-analysis. British Medical Journal. 2022;376:e067696.

Link to Publication


Maternal infection with SARS-CoV-2 has led to concerns about the potential for mother-to-child transmission in pregnancy, with uncertainty about implications for the infant. We conducted a review of the evidence published from December 2019 to April 2022. We included 643 studies (343 cohort studies, 300 case series and case reports; 44,552 mothers, 30,822 babies). Overall, 2.7% of the 24,040 babies born to mothers with SARS-CoV-2 infection tested positive for the virus. Of the 1107 SARS-CoV-2 positive babies with data on the timing of exposure and type and timing of tests, 32 had confirmed mother-to-child transmission: 20 in utero, 3 during labour, and 9 during the first days after birth. Severe maternal COVID-19 (including ICU admission and maternal death) was strongly associated with SARS-CoV-2 positivity in infants. SARS-CoV-2 positivity rates were found to be low in babies born to mothers with SARS-CoV-2 infection. Evidence suggested vertical transmission–where the virus passes from mother to baby during the period immediately before and after birth, e.g. across the placenta, in breast milk, or through direct contact during or after birth–of SARS-CoV-2 was possible, although this was rare. Severity of maternal COVID-19 disease also appeared to be associated with SARS-CoV-2 positivity in offspring.


Note: This article is a living systematic review that will be updated to reflect emerging evidence. This version is update 1 of the original article published on 16 March 2022.

Pregnancy Loss Research Group

Pregnancy Loss Research Group, Department of Obstetrics & Gynaecology, University College Cork, Fifth Floor, Cork University Maternity Hospital, Wilton, Cork, T12 YE02, Ireland,