(a) 1 - Placental Villi
2 - Umbilical cord (with its vessels)
3 - Embryo
(c) Process of delivery of the foetus (at the end of pregnancy)
The signals for parturition originate from the fully developed foetus and placenta which induce mild uterine contractions / called foetal ejection reflex , this triggers release of oxytocin from the maternal pituitary which acts on uterine muscle and causes stronger uterine contraction which stimulates further secretion of oxytocin , the stimulatory reflex between uterine contraction and oxytocin secretion continues resulting in stronger and stronger contractions leading to parturition
