Pregnant Mandy Moore Says She Had to 'Alter' Her Birth Plan After Her Platelets 'Dropped Exponentially'

Mandy Moore revealed Wednesday that she is making some changes to her birth plan "after learning that her platelet count has dropped "exponentially."

Sharing a photo from her weekly hematologist appointment on her Instagram Story, the This Is Us star said that the change in her platelets — cells that help blood clot — "altered" her initial birth plan.

"Weekly platelet check at the hematologist," Moore, 36, wrote atop a photo of herself wearing a floral dress and a grey face mask, cradling her belly. "My platelets have dropped exponentially during pregnancy and it's sadly altered my birth 'plan.' Any other pregnant folks in the same boat??"

While a drop in platelet count during pregnancy is normal, if they drop below the normal range, it's known as a condition called gestational thrombocytopenia. According to the American College of Obstetricians and Gynecologists, the condition is common and occurs in between seven and 10 percent of pregnancies at delivery.

Moore, who announced her pregnancy in September, has been open about her difficult first trimester and fertility struggles.

In an interview with Romper last month, Moore said she was "very hesitant" to believe she was pregnant because of past issues with her uterus.

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"I sort of was holding my breath until 12 weeks," she said.

Now in her third trimester, Moore has had an "it's real" moment.

"The little things kind of get me," she told Romper. "Like, I was online buying pacifiers yesterday and I just turned to my husband and I was like, It's real. There's going to be a little human that needs a pacifier."

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Since announcing that she and husband Taylor Goldsmith are expecting their first child together, a boy, Moore has been taking fans along on her pregnancy journey on Instagram.

In December, she shared a photo from 30 weeks cradling her belly and "tiny kickboxer," and last month she shared a black-and-white photo from a pregnancy shoot with the caption, "Almost there....."