With placenta-on-a-chip, researchers hope to gauge how drugs and toxins impact pregnancy

Early in her pregnancy in 2015, Nicole Hashemi wanted to know how much caffeine was safe for her to consume.

“I was actually advised not to drink a lot of caffeine,” Hashemi, an associate professor of mechanical engineering at Iowa State University, told STAT. The American College of Obstetrics and Gynecologists, for instance, advises that pregnant people consume no more than 200 milligrams per day to reduce the risk of miscarriage or preterm birth.