COVID-19 Evidence Alerts
from McMaster PLUSTM

Current best evidence for clinical care (more info)

Primary Prevention Carbone L, Trinchillo MG, Di Girolamo R, et al. COVID-19 vaccine and pregnancy outcomes: A systematic review and meta-analysis. Int J Gynaecol Obstet. 2022 Dec;159(3):651-661. doi: 10.1002/ijgo.14336. Epub 2022 Jul 29.
PICO Terms
adolescent (P) adult (P) adverse reactions; safety (O) Comirnaty; Pfizer vaccine; BNT162b2; BioNTech/Fosun Pharma; mRNA (I/C) fully vaccinated (I/C) Johnson & Johnson vaccine; Janssen Pharmaceutical Companies; Ad26.COV2.S; non-replicating viral vector (I/C) pregnant (P) Spikevax; Moderna vaccine; mRNA-1273 SARS-CoV-2; ModernaTX; mRNA (I/C) unvaccinated (I/C) Vaxzevria; AstraZeneca vaccine; ChAd0x1 nCOV-19; non-replicating viral vector; adenovirus; University of Oxford/AstraZeneca; AZD1222 (I/C)

OBJECTIVES: To explore perinatal outcomes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-vaccinated pregnant women compared with unvaccinated counterparts.

METHODS: Search was conducted using Web of Science, Scopus,, MEDLINE, Embase, OVID, and Cochrane Library as electronic databases. We included observational studies evaluating pregnant women undergoing SARS-CoV-2 vaccination and compared pregnancy and perinatal outcomes with those in unvaccinated women. Categorical variables were assessed using odds ratio (OR) with 95% confidence interval (CI), whereas for continuous variables, the results were expressed as mean difference with their 95% CI. All analyses were performed by adopting the random effect model of DerSimonian and Laird.

RESULTS: There was no difference in the probability of having a small-for-gestational-age fetus (OR 0.97, 95% CI 0.85-1.09; P = 0.570), but we observed a reduced probability of a non-reassuring fetal monitoring, a reduced gestational age at delivery, and a reduced probability of premature delivery in vaccinated pregnant women versus unvaccinated ones.

CONCLUSION: The probability of small for gestational age is similar between vaccinated and unvaccinated pregnant women, and the former also had a slightly reduced rate of premature delivery.

Discipline / Specialty Area Score
Public Health
Comments from MORE raters

Obstetrics rater

This well done systematic analysis provides powerful reassurance about the safety and efficacy of Covid vaccine for pregnant women. There was no increase in SGA and a reduction in preterm birth. Taken with other evidence, such as the protection of newborns by trans-placental passage of antibody with vaccination during pregnancy, we have strong reasons to continue urging our patients to be fully vaccinated, including relevant boosters.