Oxytocin is a hormone generated in the hypothalamus and goes to the pituitary gland. This molecule can behave as a hormone, but also as a neurotransmitter.
Oxytocin is responsible for triggering labor and dilating the cervix by causing uterine contractions. In addition, oxytocin is also involved during lactation, as it is the hormone that causes the secretion of milk by the breasts.
However, these are not the only functions of oxytocin. This hormone is essential for sexual and organ arousal in women, but also in men. Oxytocin levels increase during sexual intercourse and especially after orgasm.