(NEXSTAR) – The Centers for Disease Control and Prevention issued an alert on Wednesday urging pregnant women to get vaccinated against COVID-19.

The CDC said it “strongly recommends” the vaccine to women who are pregnant, trying to become pregnant, or wanting to have children in the future.

Data from hospitals across the country shows that about 97% of pregnant women who have been hospitalized with a confirmed case of COVID-19 were not vaccinated. In addition to the risks of serious illness and death for pregnant and recently pregnant women, the virus also puts babies at increased risk of preterm birth and admission to intensive care, according to the CDC. Stillbirths have also been reported.

Vaccination figures are lower in pregnant women than in non-pregnant women, despite the known risks.

“I strongly encourage those who are pregnant or planning to become pregnant to speak with their health care provider about the protective benefits of the Covid-19 vaccine to ensure the safety of their babies and themselves,” said the director of the CDC, Dr. Rochelle Walensky in a statement.

As of September 18, only 31% of pregnant women were fully immunized before or during their pregnancy. COVID data tracker statistics show, with distinct differences between races and ethnicities. For non-Hispanic black women, this percentage is even lower, at just 15.6%.

The lack of vaccination has resulted in more than 125,000 cases, 22,000 hospitalizations and 161 deaths among pregnant women with COVID-19, according to the CDC. Twenty-two of those deaths occurred in August alone, the highest number on record for a single month.

The CDC, which announced that there was enough data to to judge the vaccine safe for pregnant women last month, issued the alert in an attempt to “speed up” vaccinations to protect high-risk pregnant women and their unborn children.