Mother-to-child transmission (MTCT)

What is the risk of mother-to-child SARS-Cov-2 transmission a) in utero, b) intrapartum, and c) postpartum?

What is the presence and persistence of the virus in amniotic fluid, cord blood, placenta, neonatal throat swabs, vaginal fluids, faeces, serology (IgM, IgG) and breast milk?

Diagram of transmission risks to baby as explained below
Transmission risks to baby

Version 5: updated 3 August 2021

  • Overall 1.8% (95% confidence interval 1.2 to 2.5%; 140 cohort studies, 14,271 babies) of babies born to mothers diagnosed with SARS-CoV-2 infection tested positive by reverse transcriptase polymerase chain reaction (RT-PCR).
  • 0.9% of babies (95% CI 0.2 to 2.1%) tested positive within the first 24 hours of birth (32 cohorts, 2640 babies).
  • Of the 592 SARS-CoV-2 positive babies with relevant data, 14 had confirmed mother-to-child transmission: 4 in-utero live births (422 assessed), 3 in-utero foetal demise (26 assessed), two intrapartum (18 assessed), and five during the early postnatal period (70 assessed).
  • Maternal factors such as severe COVID-19 infection (odds ratio 2.4, 95% CI 1.3 to 4.4; 22 studies, 2,842 women), admission to the intensive care unit (OR 3.5, 1.7 to 6.9; 19 studies, 2,851 women), death (14.1, 4.1 to 48.0; 7 studies, 725 women), and postnatal infection of SARS-CoV-2 (5.0, 1.2 to 20.1; 12 studies, 750 women) were associated with SARS-CoV-2 positivity in offspring.
  • RT-PCR positivity rates in offspring varied between geographical regions, ranging from 0.1% (0.0% to 0.3%) in studies from North America to 5.7% (3.2% to 8.7%) in studies from Latin America and the Caribbean.
  • The types and timing of tests used to diagnose SARS-CoV-2 infection in babies varied between studies. Clinical outcomes of babies born to mothers with SARS-CoV-2 infection were inconsistently reported

To-date, there is insufficient evidence to confirm mother-to-child transmission of SARS-COV-2.

(v5.0 last search update on 3 August 2021; findings may change as new evidence emerges)

Disclaimer: The findings have not yet been peer reviewed and the sources cited should be checked. Any views expressed are those of the authors and not necessarily those of their institutions and organisations. 

Previous versions

Structured research question (PICO)

Mother-to-child transmission risk of COVID-19 infection
Population Babies born to mothers with suspected/confirmed COVID-19
Exposure In-utero, intrapartum, postpartum
Comparator -
Outcomes Offspring COVID infection status (confirmed, probable, possible, unlikely, not infected)
Viral levels in amniotic fluid, cord blood, vaginal fluids, breast milk, neonatal throat swabs, placenta; duration of viral shedding after COVID-19 symptom onset, after clinical resolution of signs/symptoms
Study design Observational studies

Findings

Full details to be published shortly. Currently undergoing peer review.