Zika virus could cause more miscarriages than initially thought

A study partly funded by NHLBI found that the Zika virus might pose a greater risk of miscarriages and stillbirths than experts initially realized, and affect women who do not know they are infected.

The research, published in Nature Medicine, found 26 percent of monkeys infected with Zika during the first trimester of pregnancy suffered miscarriage or stillbirth, despite showing few signs of infection. Zika research has previously only measured miscarriages and stillbirths in women who had symptoms of infection.

The researchers cautioned that the actual rate of miscarriage and stillbirth among pregnant women infected with Zika is likely lower than 26 percent, but still much higher than previously believed.