"Amy Schumer And Chris Fischer set pulses racing while the heavily pregnant Schumer flaunts her growing bump," she joked in the caption of a photo of her and her husband taking a walk.
She added, "Amy is still pregnant and puking because money rarely goes to medical studies for women such as hyperemesis or endometriosis."
It's been a rough pregnancy for Schumer. In November, the comedian and actress had to cancel some of her upcoming shows, and she posted a photo of herself in a hospital bed.
"I have hyperemesis and it blows. Very lucky to be pregnant but this is some bull----!" she wrote on Instagram at the time.
According to the Cleveland Clinic, hyperemesis is "extreme, persistent nausea and vomiting during pregnancy" and can lead to dehydration, which may explain the hospital stay to make sure she's keeping down fluids and nutrients.
After announcing the big news in October, Schumer has been posting about her pregnancy to help other women and share what's worked for her.
She recently praised author and economist Emily Oster for her books and how they've helped get her through this rough patch.
"The book #expectingbetter by @profemilyoster got me through pregnancy," she wrote earlier this week. "It is a fact and statistic based look at pregnancy. She is an economist at Brown University. Her follow up book #cribsheet is about children from birth to preschool. I am so grateful for her work."
Oster's findings challenge topics like letting your baby cry it out during bedtime and questioning the benefits of stay-at-home versus working parents.
"This book is about helping people use data and combining that with decision making tools," Oster told "Good Morning America" earlier this week.