From Tuesday’s Seattle Times Lungs of developing fetus may trigger start of labor :
Researchers think they’ve discovered what sends women into labor, a finding that could eventually lead to prevention of premature births.
New research in mice suggests that a substance made by babies’ lungs triggers contractions, ensuring that birth doesn’t occur until the lungs are mature.
[…]
In a study released yesterday, researchers at the University of Texas (UT) Southwestern Medical Center at Dallas report that a substance known as SP-A can initiate labor.
SP-A, which is produced by a fetus’s lungs toward the end of pregnancy, helps fight infection. It is part of a fatty mixture secreted by lung cells. This mixture, called a surfactant, coats the tiny air sacs in the lungs, preventing them from collapsing too much during respiration.
From personal experience, going into early labor with my second child, I know that medical experts monitor the baby’s lungs (via amniocentesis) in order to know whether premature labor should be halted.
Amazing, but perhaps not surprising, that the lungs – whose maturity determines how well the baby can survive – are the organ initiating labor, in a sense monitoring itself.
