what is Prostaglandins as negative feedback
As estrogen begins to stimulate uterine contractions, the uterus also produces hormones called prostaglandins. These also contribute to a decrease in progesterone levels. The release of prostaglandins helps initiate labor and, along with another hormone called relaxin, relaxes the muscles of the cervix.ut once labor is complete and the baby is no longer in the birth canal, the cervix is not being stretched anymore. This lack of the physical signal of stretching is what stops the positive feedback loop, and labor comes to an end.