Which hormone is responsible for stimulating uterine contractions during childbirth?

Oxytocin is the hormone primarily responsible for stimulating uterine contractions during childbirth. Produced by the hypothalamus and released by the posterior pituitary gland, oxytocin levels increase significantly during labor. This hormone acts on the uterine muscles, causing them to contract more forcefully and rhythmically, which aids in the process of childbirth by helping to push the baby down the birth canal.

Additionally, oxytocin plays a crucial role in the later stages of labor, contributing to the delivery of the placenta and facilitating maternal bonding and breastfeeding after the birth. The mechanism of action involves oxytocin binding to specific receptors in the uterus, leading to increased calcium concentration, which enhances muscle contraction. This process is integral for efficient labor progression and is often utilized in medical settings to induce or augment labor when necessary.