Living Cells are Shared Between Mom and Baby During Pregnancy

A tiny number of living cells can cross the placenta and be exchanged between mothers and babies. These exchanged cells can stay for decades, sometimes for life, turning pregnancy into a lasting biological connection you can’t see with the naked eye. That phenomenon is microchimerism, and it’s one of the most fascinating pieces of pregnancy science we’ve ever explored.This week we’re joined by Dr. Tara Sander Lee, a scientist with more than 25 years of experience spanning public policy, academic