HealthDay News — COVID-19 mRNA vaccines have a good safety profile in pregnancy, according to a study published online August 11 in The Lancet Infectious Diseases.

Manish Sadarangani, DPhil, from the BC Children’s Hospital Research Institute in Vancouver, British Columbia, Canada, and colleagues examined the frequency and nature of significant health events among pregnant women after COVID-19 mRNA vaccination in seven Canadian provinces and territories. Data were collected by self-reported survey after both vaccine doses for pregnant and nonpregnant women aged 15 to 49 years.

Overall, 5597 pregnant participants had received dose 1 and 3108 received dose 2, while 174,765 and 91,131 nonpregnant participants had received doses 1 and 2, respectively. The researchers found that among vaccinated pregnant women, 4.0 and 7.3% reported a significant health event after dose 1 and dose 2, respectively, compared with 3.2% of pregnant unvaccinated women. The odds of a significant health event within 7 days after vaccine dose 2 of mRNA-1273 were increased compared with pregnant unvaccinated controls in the previous 7 days (adjusted odds ratio, 4.4); no increase was seen after dose 1 of mRNA-1273 or after BNT162b2. Compared with nonpregnant vaccinated women, pregnant vaccinated women had reduced odds of a significant health event after dose 1 and 2 of any mRNA vaccination (adjusted odds ratios, 0.63 and 0.62, respectively).

“Our data provide reassuring evidence that COVID-19 mRNA vaccines are safe in pregnancy, with lower rates of significant adverse events following immunization in pregnant people than in nonpregnant vaccine recipients for both mRNA vaccines used in Canada,” the authors write.

Several authors disclosed financial ties to pharmaceutical companies, including Pfizer and Moderna.

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