How do babies breathe in the womb?
Babies do not actually breathe in the womb—at least, not in the usual sense. Fetal lungs are not fully functional, and are not even able to fully expand, until after birth. During the later stages of gestation, the fetus may “practice” breathing by inhaling and exhaling amniotic fluid. The fetal lungs do not process the amniotic fluid, the way fully formed lungs process air, but experts believe this “breathing” is important to fetal lung development. The fetus gets all of its oxygen and nutrients through the placenta and umbilical cord—a process called fetal circulation.
