A new large-scale study has found no increase in pregnancy complications following vaccination against Covid-19.

Earlier studies have shown that pregnant women who develop Covid-19 are more likely to become seriously ill and require intensive care compared to women who are not pregnant. The virus can also lead to complications such as premature labour. As a result, vaccination is recommended for this group.

However, according to the study’s co-first author, Dr Anne Örtqvist Rosin, a researcher at the Karolinska Institutet in Sweden, vaccination rates still tend to be lower among pregnant women, “so it’s likely that there’s some concern about how the vaccines affect the pregnant individual and the foetus”.

“When the vaccines were produced, pregnant women were not included in the large clinical studies and until now, there have been no population-based data about any risk there might be to them,” she explained.

The researchers studied data on over 157,000 women who gave birth in Sweden and Norway between January 2021 and January 2022. Of these almost one in five (18%) had been vaccinated against Covid-19.

The study found that vaccinated women did not face an increased risk of experiencing complications during their pregnancy compared to unvaccinated women.

“The results are reassuring and can hopefully make pregnant individuals more willing to get vaccinated,” Dr Örtqvist Rosin suggested.

The researchers also noted that a potential advantage of vaccination during pregnancy is that the antibodies formed pass through the placenta, providing the newborn baby with a certain degree of protection against Covid-19.

“We’re now planning to study how long this protection lasts and if SARS-CoV-2 infection or vaccination during pregnancy has any other lasting effects on the child’s health,” added study author, Prof Olof Stephansson, also of the Karolinska Institutet.

The study is published in the journal, JAMA, and can be viewed here.