COVID-19 Evidence Alerts
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Prognosis Norman M, Naver L, Soderling J, et al. Association of Maternal SARS-CoV-2 Infection in Pregnancy With Neonatal Outcomes. JAMA. 2021 May 25;325(20):2076-2086. doi: 10.1001/jama.2021.5775.
Abstract

Importance: The outcomes of newborn infants of women testing positive for SARS-CoV-2 in pregnancy is unclear.

Objective: To evaluate neonatal outcomes in relation to maternal SARS-CoV-2 test positivity in pregnancy.

Design, Setting, and Participants: Nationwide, prospective cohort study based on linkage of the Swedish Pregnancy Register, the Neonatal Quality Register, and the Register for Communicable Diseases. Ninety-two percent of all live births in Sweden between March 11, 2020, and January 31, 2021, were investigated for neonatal outcomes by March 8, 2021. Infants with malformations were excluded. Infants of women who tested positive for SARS-CoV-2 were matched, directly and using propensity scores, on maternal characteristics with up to 4 comparator infants.

Exposures: Maternal test positivity for SARS-CoV-2 in pregnancy.

Main Outcomes and Measures: In-hospital mortality; neonatal resuscitation; admission for neonatal care; respiratory, circulatory, neurologic, infectious, gastrointestinal, metabolic, and hematologic disorders and their treatments; length of hospital stay; breastfeeding; and infant test positivity for SARS-CoV-2.

Results: Of 88?159 infants (49.0% girls), 2323 (1.6%) were delivered by mothers who tested positive for SARS-CoV-2. The mean gestational age of infants of SARS-CoV-2-positive mothers was 39.2 (SD, 2.2) weeks vs 39.6 (SD, 1.8) weeks for comparator infants, and the proportions of preterm infants (gestational age <37 weeks) were 205/2323 (8.8%) among infants of SARS-CoV-2-positive mothers and 4719/85?836 (5.5%) among comparator infants. After matching on maternal characteristics, maternal SARS-CoV-2 test positivity was significantly associated with admission for neonatal care (11.7% vs 8.4%; odds ratio [OR], 1.47; 95% CI, 1.26-1.70) and with neonatal morbidities such as respiratory distress syndrome (1.2% vs 0.5%; OR, 2.40; 95% CI, 1.50-3.84), any neonatal respiratory disorder (2.8% vs 2.0%; OR, 1.42; 95% CI, 1.07-1.90), and hyperbilirubinemia (3.6% vs 2.5%; OR, 1.47; 95% CI, 1.13-1.90). Mortality (0.30% vs 0.12%; OR, 2.55; 95% CI, 0.99-6.57), breastfeeding rates at discharge (94.4% vs 95.1%; OR, 0.84; 95% CI, 0.67-1.05), and length of stay in neonatal care (median, 6 days in both groups; difference, 0 days; 95% CI, -2 to 7 days) did not differ significantly between the groups. Twenty-one infants (0.90%) of SARS-CoV-2-positive mothers tested positive for SARS-CoV-2 in the neonatal period; 12 did not have neonatal morbidity, 9 had diagnoses with unclear relation to SARS-CoV-2, and none had congenital pneumonia.

Conclusions and Relevance: In a nationwide cohort of infants in Sweden, maternal SARS-CoV-2 infection in pregnancy was significantly associated with small increases in some neonatal morbidities. Given the small numbers of events for many of the outcomes and the large number of statistical comparisons, the findings should be interpreted as exploratory.

Ratings
Discipline / Specialty Area Score
Obstetrics
Pediatric Neonatology
Infectious Disease
Family Medicine (FM)/General Practice (GP)
Comments from MORE raters

Infectious Disease rater

The study, which used the data of a nationwide cohort of infants in Sweden to evaluate the effects of maternal SARS-CoV-2 infection in pregnancy, demonstrated a significant increase in the risk of a few neonatal morbidities. Though not significant, the almost 2.6 fold increase in the odds of mortality (with the lower bound of 95% CI just crossing the null value of 1) is worrisome.

Pediatric Neonatology rater

This is a nation wide cohort of infants in Swede. Maternal SARS CoV2 infection in pregnancy was significantly associated with small increases in some neonatal morbidities. As the authors conclude that given the small numbers of events for many of the outcomes and the large number of statistical comparisons, the findings should be interpreted as exploratory. I don't think that this study had significant meanings, as compared other similar studies with large number of participants.

Pediatric Neonatology rater

A large, national cohort with a good established data base is much more useful than the many small case series, even when those have been merged into meta-analyses. This paper is important for Neonatologists.