Finland is recommending that recipients of a coronavirus vaccine should avoid becoming pregnant for up to two months after receiving the shots.
The THL vaccine programme's Chief Physician Hanna Nohynek says recommendations are based on a forward-looking precautionary principle.
Vaccine manufacturers Pfizer and BioNTech have warned that the possible effects of their vaccines on foetuses have not yet been sufficiently studied.
"They are considering whether the inflammatory effect triggered by the vaccine could have an impact during the very early stages of pregnancy," Nohynek says.
Animal trials using the vaccines have not given rise to any suggestion of risk to a foetus.
"There are no indications of malformation or anything else that could be cause for alarm," Nohynek says.
According to Nohynek, a safety margin of two months is more than sufficient. Inflammation caused by the body's reaction to a vaccine usually lasts for no more than a couple of weeks.
"So a period of two months is that length due to an abundance of caution," Nohynek says.
Vaccine studies extended to pregnant women
Unlike the influenza vaccine, it is not yet recommended that all pregnant women get the coronavirus vaccine, but it can be given to pregnant women after an assessment of their healthcare needs.
If a pregnant woman is in a high risk group for coronavirus, for example because of underlying health conditions or her job - working, for example, in the health and social care sectors - she can be vaccinated if she so wishes.
Vaccine studies worldwide are currently being extended to include pregnant women as well.
"In the United States, a group of nearly a thousand women have taken the coronavirus vaccine at different stages of their pregnancy, and from there we will get valuable research data," says Hanna Nohynek.
Vaccines do not usually come with a two-month waiting period for pregnancy. The influenza vaccine is actively recommended both for those planning to become pregnant and those who are already pregnant.
Despite the recommendation, THL's Hanna Nohynek urges clinics to continue to provide care to pregnant women who have received the vaccine.
"It is not appropriate for obstetric and reproductive care to be withdrawn due to vaccination," she says.