This is a plain English summary of an original research article. The views expressed are those of the author(s) and reviewer(s) at the time of publication.
Recent research provides evidence to back the safety and effectiveness of the COVID-19 vaccine for pregnant women. Compared with women who were not vaccinated, women vaccinated during pregnancy had a reduced risk of:
- blood pressure disorders during pregnancy
- giving birth by caesarean section
- their newborn needing admission to intensive care.
The issue: should pregnant women have the COVID-19 vaccine?
Pregnant women with COVID-19 are more likely to develop severe COVID-19 and related ill health than non-pregnant women of similar age. Research has shown that COVID-19 vaccines reduce death and illness severity; however, most studies excluded pregnant women. Information was therefore lacking on the safety and effectiveness of these vaccines during pregnancy.
Researchers analysed evidence on the safety and effectiveness of COVID-19 vaccines in women before or during pregnancy.
What’s new?
This research was based on studies published between 2019 and 2023 from countries around the world. All followed groups of women over time and compared outcomes among those who received the vaccine with those who did not.
The researchers considered studies that adjusted for maternal age, diabetes, high blood pressure, body mass index, gestational age and education. They assessed the impact of vaccination on COVID-related health, pregnancy and baby outcomes.
Compared to unvaccinated women, those who received a vaccine:
- were less likely (61% less) to develop COVID-19 during pregnancy (4 studies including 23,927 women) and much less likely (94% less) to be admitted to hospital because of COVID-19 (2 studies including 868 women)
- had less chance (12% less) of high blood pressure or other blood pressure disorders during pregnancy (2 studies including 115,085 women)
- were less likely (9% less) to have a caesarean section (6 studies including 30,192 women)
- had babies that were less likely (8% less) to be admitted to neonatal intensive care units (2 studies including 54,569 women)
- had a higher chance (17% more) of developing gestational diabetes (2 studies involving 115,085 women).
Pain at injection site was reported by most women (77%) who received the vaccine (11 studies involving 27,195 women). Other side-effects were less frequent, for instance fatigue was reported by 29% of women in 14 studies involving 72,671 women.
Why is this important?
The findings mirror those from studies carried out in the general population, and show that, among pregnant women, the COVID-19 vaccine reduced risks related to COVID-19. In addition, the vaccine reduced the risk of common pregnancy complications such as high blood pressure, caesarean sections and neonatal admissions.
The increased risk of gestational diabetes with vaccination was found in 2 different populations in a single study. The researchers say this link needs to be explored further.
Many of the studies carried a moderate or severe risk of bias. This analysis could not establish whether the timing of the vaccine during pregnancy affected outcomes. Further, data are still lacking about long-term effects of the vaccine on mothers such as low platelet levels (thrombocytopenia), which can increase bruising and bleeding) and inflamed heart muscle (myocarditis).
What’s next?
The findings have been used to inform healthcare professionals and women about the safety of the vaccine.
You may be interested to read
This is a summary of: Fernández-García S, and others. Effectiveness and safety of COVID-19 vaccines on maternal and perinatal outcomes: a systematic review and meta-analysis. BMJ Global Health 2024; 9: e014247.
A press release from the University of Birmingham about this research: COVID-19 vaccination in pregnancy lowers risk of cesarean section, hypertension.
Research on birth outcomes among women vaccinated against COVID-19 before pregnancy: Suseeladevi AK, and others. COVID-19 vaccination and birth outcomes of 186,990 women vaccinated before pregnancy: an England-wide cohort study The Lancet Regional Health Europe 2024; 45: 101025.
Research about the impact of COVID-19 and vaccination on pregnancy outcomes: Raffetti E, and others. COVID-19 diagnosis, vaccination during pregnancy, and adverse pregnancy outcomes of 865,654 women in England and Wales: a population-based cohort study. The Lancet Regional Health Europe 2024; 45: 101037.
The PregCOV-19LSR group conducts reviews of research about the impact of COVID-19 on pregnancy.
Funding: This study was funded by the NIHR Birmingham Biomedical Research Centre.
Conflicts of Interest: No relevant conflicts were declared. Full disclosures are available on the original paper.
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