Zika Infection Causes Birth Defects in 5 Percent of Cases

New findings about Zika infections indicate that some babies may escape the most serious birth defects associated with the disease.

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There's no doubt about it: The Zika virus is a major danger facing pregnant women and their unborn babies across the globe. The mysterious virus has been linked to birth defects, most notably microcephaly, which causes babies to be born with small heads and incomplete brain development—in light of this, pregnant women have been urged to avoid travel to any area with active transmission of the virus.

But as Zika's active zone spreads, scientists work to figure out how the virus functions, and how it can be stopped—and some recently released news gives to-be mothers who have been exposed to the virus some hoop.

According to a new report from the Centers for Disease Control and Prevention, 5 percent of women who had confirmed cases of the Zika virus in the U.S. gave birth to babies with Zika-linked birth defects. The researchers studied 2,550 women who were diagnosed with a possible Zika infection (the virus was confirmed in about 1,500 of these cases) to come this finding. 

While experts caution that there's no point in pregnancy during which Zika exposure is safe, it appears there may be slightly increased risk earlier in the pregnancy: About 8 percent of the babies born to mothers infected in their first trimesters showed birth defects—this number dropped to 5 percent among moms exposed during their second trimesters, and just 4 percent among those who contracted Zika in their third trimesters.

This news may serve as reassurance to many moms-to-be out there, but let's make one thing very clear: There is still a significant risk associated with Zika exposure. If you can avoid entering a Zika zone, that really is the way to go—and if you live in or must travel to an area the CDC is warning against visiting, speak with a doctor about all the ways in which you can protect yourself. It's also important to remember that the virus is still being studied extensively—and researchers may find additional information about issues that present later in life among babies who suffered fetal exposure.

The CDC reiterates that point. “As these latest findings illustrate, Zika virus poses a serious threat to pregnant women and their babies, regardless of when the infection occurs during the pregnancy,” CDC acting director Anne Schuchat, M.D., said, according to the report. “Women in the U.S. territories and elsewhere who have continued exposure to mosquitoes carrying Zika are at risk of infection. We must remain vigilant and committed to preventing new Zika infections.”