As President Obama waits on Congress to get him a better Zika funding number, more pregnant women in the United States are testing positive for the virus that causes birth defects.

FOX's Eben Brown reports from Miami:

The number of pregnant women in U.S. states and territories now being watched for negative effects of zika virus has jumped in the past week from just over a 100 to nearly 300. But there isn't an increase in actual cases:

(Dr. Honein) "As the data accumulated about the risk of asymptomatic infections, it seemed more and more important to be very transparent and share publicly the numbers of the full number of pregnant women at risk of adverse outcomes."

CDC's Dr. Margaret Honein says up until now, they only counted pregnant women who became physically ill likely due to zika. The virus is blamed for birth defects.

Eben Brown, FOX News.

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