Are planning pregnancy and worried about taking COVID-19 vaccines for fear of complications? Take heart, a new study shows no increased risk of early or late miscarriage as a result of male or female partners getting a COVID vaccine prior to conceiving.

Multiple studies have shown that the COVID-19 vaccines do not lead to infertility or pregnancy complications such as miscarriage, but many people are still wary of adverse effects from the vaccine on pregnancy.

The new study, published in the journal Human Reproduction, is the first to evaluate the risk of early miscarriage (less than eight weeks’ gestation) following preconception COVID vaccination, as well as the first to evaluate male vaccination and miscarriage. 

The researchers at Boston University in the US hope these results provide useful information for individuals planning to become pregnant, as well as their healthcare providers.

“These findings should be replicated in other populations, but are reassuring for couples who are planning pregnancy,” said lead author Jennifer Yland from the varsity's School of Public Health.

"The rate of miscarriage among vaccinated individuals was not only comparable with that of participants who conceived before the pandemic, but our data indicated a slightly lower risk of miscarriage among vaccinated individuals compared to unvaccinated individuals," Yland said.

For the study, the team analysed survey data on COVID-19 vaccination and miscarriage on 1,815 female individuals in the US and Canada who were followed from December 2020 through November 2022. 

They were observed from their first positive pregnancy test until a miscarriage or other event (such as induced abortion, ectopic pregnancy, or 20 weeks gestation) -- whichever occurred first.

Risk of miscarriage was 26.6 per cent among unvaccinated female participants, 23.9 per cent among female participants who had received one dose of the vaccine before conception, 24.5 per cent among those who completed a full primary series before conception, 22.1 per cent among those who completed the vaccine series three months before conception, and 20.1 per cent among those who received only one dose of a two-dose vaccine before conception. 

Federal health officials continue to recommend COVID-19 vaccination to individuals planning to conceive and stress that the benefits of receiving a COVID-19 vaccine outweigh the potential risks of vaccination during preconception or pregnancy.