From where do the parturition signals arise—mother or foetus? Mention the main hormone involved in parturition.

(N/A) Parturition is a complex process regulated by a combination of neural and hormonal mechanisms.
The signals for parturition originate from the fully developed foetus and the placenta, which induce mild uterine contractions known as the $foetal \text{ } ejection \text{ } reflex$.
$Oxytocin$ is the primary hormone involved in parturition. It acts on the uterine muscles to cause stronger uterine contractions, which ultimately lead to the expulsion of the baby from the uterus through the birth canal.