Oxytocin is a mammalian hormone that acts primarily as a neuromodulator in the brain.
It is best known for roles in female reproduction:
1) it is released in large amounts after distension of the cervix and uterus during labor, and
2) after stimulation of the nipples, facilitating birth and breastfeeding.
Recent studies have begun to investigate oxytocin's role in various behaviors, including orgasm, social recognition, pair bonding, anxiety, and maternal behaviors. For this reason, it is sometimes referred to as the "love hormone"