The 33-year-old said she 'got a little hot' and was taken to the hospital.
In the end, both mother and daughter are OK.
Still, CNN anchor Poppy Harlow, who announced her first pregnancy in late November, gave viewers a scare when she passed out live on air on Monday morning while discussing a breaking news story.
Though you do not see Harlow onscreen, you can hear her speech start to slur and a gasp from off-screen:
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“For all of you on Twitter, who are asking if I’m OK, thank you so much. I got a little hot and I passed out for a moment,” the 33-year-old explained when she reappeared on air minutes later. “I am fine.”
Harlow reiterated this when she later tweeted that she had been taken to the hospital. “Our little girl due this spring is doing just fine,” she reassured her followers. “Was a scare but we are both ok.”
Update from the hospital -- our little girl due this spring is doing just fine. Was a scare but we are both ok. Thank you all so much!
— Poppy Harlow (@PoppyHarlowCNN) December 28, 2015One possible explanation? According to the Mayo Clinic, changes in the circulation system during pregnancy can lead to lightheadedness and dizziness.
Speaking of babies, here are seven celebrity offspring to expect in 2016: