(NEXSTAR) – Moderna’s COVID-19 vaccine is “not recommended” for pregnant women, according to a news release Tuesday from the World Health Organization.

“While pregnancy puts women at a higher risk of severe COVID-19, the use of this vaccine in pregnant women is currently not recommended, unless they are at risk of high exposure (e.g. health workers),” the release states.

The Centers for Disease Control and Prevention said that while COVID vaccines in pregnant women haven’t been studied clinically, they believe the Moderna vaccine is unlikely to pose a risk since it is an mRNA vaccine, not a live vaccine, and will be degraded quickly “by normal cellular processes.”

The WHO and CDC recommend that the vaccine be offered to women who are pregnant or breastfeeding and in a group recommended for vaccination, such as healthcare workers. Women who receive it should not stop breastfeeding because of the vaccine.

Anyone under 18 should not yet receive the vaccine pending further tests, according to the organization, and older people with an expected life span of three months or less should be individually assessed.

People who have already contracted COVID-19 can get the vaccine, but “individuals may wish to defer their own COVID-19 vaccination for up to six months from the time of SARS-CoV-2 infection.”

The Moderna vaccine has been deemed safe for people with medical conditions associated with risk of severe disease, and is also recommended after counseling for HIV-positive and immunocompromised recipients.

The WHO stated that the vaccine has been shown to be 92-percent effective against COVID-19 – including against new variants such as B.1.1.7 and the 501Y.V2 – but the full duration of immunity and ability to stop infection and transmission is still being studied.

In the meantime, basic health measures such as masking, physical distancing, hand washing, respiratory and cough hygiene, avoidance of crowds and good ventilation are recommended.