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Published on: July 31, 2021
Early exploration of COVID-19 vaccination safety and effectiveness during pregnancy: interim descriptive data from a
Inna Bleicher1, Einav Kadour-Peero2, Lena Sagi-Dain3
1Department of Obstetrics and Gynecology, Bnai -Zion Medical Center, Haifa, Israel.
Insights
The Pfizer-BioNTech COVID-19 vaccine did not increase pregnancy complications in vaccinated pregnant women. Vaccination significantly reduced the risk of contracting COVID-19 during pregnancy.
Area of Science:
- Obstetrics and Gynecology
- Vaccinology
- Infectious Diseases
Background:
- A massive vaccination program using the Pfizer-BioNTech (BNT162b2) mRNA vaccine commenced in December 2020.
- The vaccine was initially prioritized for high-risk populations, including healthcare workers and pregnant women.
- There was a need to evaluate the short-term safety and efficacy of this vaccine in pregnant individuals.
Purpose of the Study:
- To compare short-term pregnancy outcomes between vaccinated and unvaccinated pregnant women.
- To assess the incidence of composite pregnancy complications in both groups.
- To determine the effectiveness of the vaccine in preventing COVID-19 infection among pregnant women.
Main Methods:
- A prospective observational cohort study was conducted.
- Pregnant women were recruited via online questionnaires distributed through medical groups on social media platforms.
- Data on pregnancy complications and COVID-19 infection were collected through initial and follow-up questionnaires administered one month apart.
Main Results:
- The vaccination rate among participants increased from 25.5% to 62% within one month.
- No significant difference in the rate of composite pregnancy complications was observed between vaccinated (15.8%) and unvaccinated (20.1%) groups (p=0.37).
- The risk of COVID-19 infection was significantly lower in the vaccinated group (1.5% vs 6.5%, p=0.024).
Conclusions:
- The mRNA COVID-19 vaccine (Pfizer-BioNTech) appears safe for use during pregnancy, with no observed increase in short-term pregnancy complications.
- Vaccination with the Pfizer-BioNTech vaccine is effective in preventing COVID-19 infection in pregnant women.
- These findings support the recommendation of COVID-19 vaccination for pregnant individuals.
Objective:
During December 2020, a massive vaccination program was introduced in our country. The Pfizer-BioNTech, BNT162b2 vaccine was first offered exclusively to high-risk population, such as medical personnel (including pregnant women). In this study we compare short term outcomes in vaccinated vs. non-vaccinated pregnant women.
Methods:
In this prospective observational cohort study, vaccinated and non-vaccinated pregnant women were recruited using an online Google forms questionnaire targeting medical groups on Facebook and WhatsApp. A second questionnaire was sent one month after the first one for interim analysis. Our primary outcome was composite complications in vaccinated and non-vaccinated groups, considered any of the following: vaginal bleeding, pregnancy loss, hypertension, gestational diabetes, and preterm birth. Secondary outcomes included: vaccine side effects, diagnosis of COVID-19 since the last questionnaire, prevalence of vaccinated participants, and reasons for refusal to be vaccinated.
Results:
Overall, 432 women answered the first questionnaire, of which 326 responses were received to the second questionnaire. Vaccination rate increased from 25.5% to 62% within a month. Maternal age, gestational age at enrollment, nulliparity and number of children were similar in both groups. The rate of composite pregnancy complications was similar between vaccinated and non-vaccinated group (15.8% vs 20.1%, p = 0.37), respectively. The risk for COVID-19 infection was significantly lower in the vaccinated group (1.5% vs 6.5%, p = 0.024, Odds Ratio: 4.5, 95% confidence interval 1.19-17.6).
Conclusions:
mRNA vaccine during pregnancy does not seem to increase the rate of pregnancy complications and is effective in prevention of COVID-19 infection.
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