Induction of Labour

 

In different mammals, signals from either the mother or the fetus can induce labour. We do not know what the trigger is in humans, though some possibilities include:

 

Prostaglandins (PGE2 and PGF2alpha) are produced in the endometrium, myometrium, and chorioaminon, and levels increase near term and further in labour. PGE2 is associated with cervical ripening due to collagen lysis and water accumulation.

PGE2 analogue dinoprostone and PGE1 analogue misoprostol are used as cervical ripening agents.

 

Oxytocin receptors in the uterus increase in number as term approaches, but serum levels increase siginificantly only once labour has begun.