What Triggers Labor?

Oooh I love having nerdy birth-related conversations with my friends!  It brings up such good points that I then go investigate, such as this post!

Question: Does the baby induce labor?

I always assumed it was your glands producing oxytocin that induced labor, but I guess I never thought about what made your brain produce the oxytocin!

Apparently, the experts aren't sure what causes labor to begin. Some researchers now believe that the baby actually starts labor by sending a signal to the mother's body that causes labor to start.

Here are two theories:

One theory is that the baby's lungs secrete an enzyme or chemical when they are fully developed. This causes prostaglandins to be released into the mother's system. The prostaglandins then trigger changes in the cervix and contractions. Prostaglandins are sometimes used to induce labor.

Another theory is that the baby's adrenal glands send a signal to start labor. When the baby is ready to be born, the adrenal glands produce hormones. These hormones cause hormonal changes in the mother. These changes are responsible for the process that starts labor.

I couldn't find the Discovery Health show that caused the question in the first place. If I find any other information on this I'll post it!