Final answer:
Oxytocin is the hormone that stimulates uterine contractions during childbirth, working through a positive feedback mechanism to increase contractions until the baby is born.
Step-by-step explanation:
The hormone responsible for uterine contractions during childbirth is oxytocin. This endocrine hormone is secreted by the posterior pituitary gland. Late in pregnancy, the uterus becomes highly sensitive to oxytocin due to an increase in the number of oxytocin receptors. During labor, oxytocin initiates uterine contractions that push the baby toward the cervix, leading to its stretching. This stretching acts as a stimulus for the pituitary gland to release more oxytocin, resulting in stronger contractions, a process known as a positive feedback mechanism. This cycle of events continues until the baby is born.
The hormone that stimulates uterine contractions during childbirth is oxytocin. Oxytocin is a peptide-derived hormone that is secreted by the pituitary gland and functions during childbirth to stimulate uterine contractions and dilation of the cervix. As the fetus completes its development, the uterus becomes more sensitive to oxytocin, resulting in stronger and more frequent contractions. Oxytocin is continuously released throughout childbirth through a positive feedback mechanism, until the birth is complete.