"Today" show co-host Savannah Guthrie says she's pregnant and will be skipping the upcoming Olympic Games in Rio de Janeiro because of the Zika virus.

Guthrie made the announcement on the NBC program Tuesday morning. She cited doctors' advice in deciding to skip the Olympics. NBC had announced in April that Guthrie would co-host the opening ceremony of the Rio Games on Aug. 5.

NBC Universal has stated employees who are concerned about making the trip to Brazil can opt out.

“We’ve created a transparent culture here where people feel very comfortable raising a hand and saying, ‘You know what? I’d rather not make this trip,’” Noah Oppenheim, NBC News Senior Vice President, told The Hollywood Reporter.

Zika is known to cause birth defects, including microcephaly, in which the baby's head is smaller than expected because the brain hasn't developed properly. The virus is now in 60 countries, with Olympic host Brazil the hardest-hit nation.

Guthrie says her second child with husband Michael Feldman is due in December. The couple's first child, a girl, was born in August 2014.

The Associated Press contributed to this report.