A pregnant womanstands outside a maternity hospital in Singapore, Sept. 1, 2016. Singapore reported the first case of pregnant woman with Zika virus infection, among 24 newly reported cases of locally transmitted Zika virus, the country's Health Ministry said on Wednesday. (Xinhua/Then Chih Wey)

WASHINGTON, April 4 (Xinhua) -- About one in 10 of women in the United States who were infected with the Zika virus during pregnancy had a fetus or baby with birth defects, U.S. health authorities said Tuesday.

Of the 250 pregnant women who had confirmed Zika infection in 2016, 24 had a fetus or baby with one or more birth defects thought to be linked to the Zika infection, according to a new report released by the U.S. Centers for Disease Control and Prevention (CDC).

The findings from this report confirm the serious threat posed by Zika virus infection during pregnancy and the critical need for pregnant women to continue taking steps to prevent Zika virus exposure through mosquito bites and sexual transmission, the CDC said.

"Zika virus can be scary and potentially devastating to families. Zika continues to be a threat to pregnant women across the U.S.," CDC Acting Director Anne Schuchat said in a statement. "With warm weather and a new mosquito season approaching, prevention is crucial to protect the health of mothers and babies."

In 2016, a total of 1,297 pregnant women with possible possible Zika infection were reported to the U.S. Zika Pregnancy Registry, the report said. Most of these women acquired Zika virus infection during travel to an area with Zika.

Of the 1,000 pregnancies that were completed by the end of the year, more than 50, or five percent, had Zika-related birth defects.

The proportion was higher among complected pregnancies with confirmed Zika infection, with about 10 percent reporting had a fetus or baby with birth defects.

Confirmed infections in the first three months of pregnancies posed the highest risk, with about 15 percent reporting have Zika-related birth defects.

The report also found that about one in three babies with possible congenital Zika infection had no report of Zika testing at birth and that only one in four babies with possible congenital Zika infection were reported to have received brain imaging after birth.

Zika is mainly transmitted via the bite of infected Aedes aegypti mosquitoes but also can be transmitted sexually.

Zika infection during pregnancy can cause serious damage to the brain and microcephaly in developing fetuses. It also can lead to congenital Zika syndrome in babies, a pattern of birth defects that includes brain abnormalities, vision problems, hearing loss, and problems moving limbs.

Babies may also appear healthy at birth but have underlying brain defects or other Zika-related health problems.

Currently there is no licensed vaccine to prevent disease caused by Zika infection.