About These Numbers

What these updated numbers show

• These updated numbers reflect counts of pregnant women in the United States with any laboratory evidence of possible Zika virus infection, with or without symptoms. Pregnant women with laboratory evidence include those in whom viral particles have been detected and those with evidence of an immune reaction to a recent virus that is likely to be Zika.
• This information will help healthcare providers as they counsel pregnant women affected by Zika and is essential for planning at the federal, state, and local levels for clinical, public health, and other services needed to support pregnant women and families affected by Zika.

What these new numbers do not show

• These new numbers are not comparable to the previous reports. These updated numbers reflect a different, broader population of pregnant women.
• These updated numbers are not real time estimates. They will reflect the number of pregnant women reported with any laboratory evidence of possible Zika virus infection as of 12 noon every Thursday the week prior; numbers will be delayed one week.

Where do these numbers come from?

These data reflect pregnant women in the US Zika Pregnancy Registry and the Zika Active Pregnancy Surveillance System in Puerto Rico. CDC, in collaboration with state, local, tribal and territorial health departments, established these registries for comprehensive monitoring of pregnancy and infant outcomes following Zika virus infection.

The data collected through these registries will be used to update recommendations for clinical care, to plan for services and support for pregnant women and families affected by Zika virus, and to improve prevention of Zika virus infection during pregnancy.

What are the outcomes for these pregnancies?

Visit CDC’s webpage for updated counts of poor pregnancy outcomes related to Zika. Most of the pregnancies monitored by these systems are ongoing. CDC will not report outcomes until pregnancies are complete.