Question

Which hormone is secreted by the maternal posterior pituitary and causes vigorous uterine contractions?

Options

• Corticosteroids

• Oxytocin

• Relaxin

• ACTH

Answer 1

Oxytocin is secreted by the maternal posterior pituitary (neurohypophysis) and causes vigorous uterine contractions. It is central to the positive feedback mechanism of parturition, where stronger contractions lead to more oxytocin release, further intensifying contractions until delivery is complete.