COVID-19 vaccines made using mRNA technology do not cause pregnancy complications for expectant mothers and their babies, the European Union's drug regulator said on Tuesday, following a detailed review of several studies.

The review based on studies involving around 65,000 pregnancies at different stages did not find any sign of higher risk of complications, miscarriages, preterm births or severe side-effects on the unborn babies from mRNA shots, the European Medicines Agency said.

Pfizer and German partner BioNTech, as well as Moderna, currently supply such vaccines to the European Union.

While the EMA acknowledged some limitations in the data, it said results were consistent across studies.

"The benefits of receiving mRNA COVID-19 vaccines during pregnancy outweigh any possible risks for expectant mothers and unborn babies," the agency said.

The review by an internal team also found that COVID-19 shots are as effective at cutting the risk of hospitalization and death in pregnant people as in non-pregnant people.

Several EU countries have already endorsed the use of COVID-19 vaccines for pregnant people, and the EMA's backing of mRNA shots is likely to bolster vaccination campaigns in smaller nations that rely on the regulator's scientific expertise.