Infants Born to Mothers Who Were SARS-CoV-2 Positive during Pregnancy and Admitted to Neonatal Intensive Care Unit

Neonatology. 2022;119(5):619-628. doi: 10.1159/000526313. Epub 2022 Sep 9.


Introduction: Our objective was to compare neonatal outcomes and resource use of neonates born to mothers with SARS-CoV-2 positivity during pregnancy with neonates born to mothers without SARS-CoV-2 positivity.

Methods: We conducted a two-country cohort study of neonates admitted between January 1, 2020, and September 15, 2021, to tertiary neonatal intensive care unit (NICU) in Canada and Sweden. Neonates from mothers who were SARS-CoV-2 positive during pregnancy were compared with three randomly selected NICU neonates of mothers who were not test-positive, matched on gestational age, sex, and birth weight (±0.25 SD). Subgroup analyses were conducted for neonates born <33 weeks' gestation and mothers who were SARS-CoV-2 positive ≤10 days prior to birth. Primary outcome was duration of respiratory support. Secondary outcomes were in-hospital mortality, neonatal morbidity, late-onset sepsis, receipt of breast milk at discharge, and length of stay.

Results: There were 163 exposed and 468 matched neonates in Canada, and 303 exposed and 903 matched neonates in Sweden. There was no statistically significant difference in invasive or noninvasive respiratory support durations, mortality, respiratory and other neonatal morbidities, or resource utilizations between two groups in both countries in entire cohort and in subgroup analyses. Receipt of breast milk at discharge was lower in the Canadian neonates of mothers who were SARS-CoV-2 positive ≤10 days before birth (risk ratio 0.68, 95% CI: 0.57-0.82).

Conclusion: Maternal SARS-CoV-2 positivity was not associated with increased durations of respiratory support, morbidities, mortality, or length of hospital stay in Canada and Sweden among neonates admitted to tertiary NICU.

Keywords: COVID-19; Infant; Maternal positivity; Outcomes; Preterm.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • COVID-19* / epidemiology
  • Canada / epidemiology
  • Cohort Studies
  • Female
  • Humans
  • Infant, Newborn
  • Infectious Disease Transmission, Vertical
  • Intensive Care Units, Neonatal
  • Male
  • Pregnancy
  • Pregnancy Complications, Infectious* / epidemiology
  • Pregnancy Outcome
  • SARS-CoV-2

Grants and funding

No specific funding was received for this study. Prakesh Shah has received funding for the Canadian Preterm Birth Network from the Canadian Institutes of Health Research (APR-126340) which supports activities of Mother-Infant Care Research Center. Mikael Norman was supported by grants from a regional agreement on clinical research (ALF) between Region Stockholm and Karolinska Institutet (ALF 2020-0443) and by the Childhood Foundation of the Swedish Order of Freemasons. The Swedish Neonatal Quality Register and the Swedish Pregnancy Register are funded by the Swedish Government (Ministry of Health and Social Affairs) and the body of Regional Health Care Providers (County Councils). The funding body played no role in the design or conduct of the study; the collection, management, analysis, or interpretation of the data; the preparation, review, or approval of the manuscript; or the decision to submit the manuscript for publication.