Serious birth defects afflict one in 10 Zika pregnancies, shocking new study reveals

About 1 in 10 pregnant women infected with Zika in the United States last year had a baby or foetus with serious birth defects, according to the startling results of study released Tuesday that represents the largest and most comprehensive analysis of Zika’s consequences for pregnant women.

Women infected during the first trimester of pregnancy had an even higher risk of birth defects, about 15 per cent, according to the analysis by the Centers for Disease Control and Prevention.

The estimates are higher than US health officials have previously reported and underscore the serious risk for birth defects posed by Zika virus infection during pregnancy. With warm weather, a new mosquito season and summer travel approaching, prevention is crucial to protecting the health of mothers and babies, said Anne Schuchat, the CDC’s acting director.

It may seem like Zika is last year’s problem, she said, but that is not true, and pregnant women, their male partners, and clinicians can’t be complacent.

“Don’t let this outbreak be your family’s heartbreak,” she said.

Most infections are spread by mosquitoes, but the virus also can be transmitted through sex and bodily fluids.