Maternity Nursing: Antepartum Q 33



The pituitary hormone that stimulates the secretion of milk from the mammary glands is:
  
     A. Prolactin
     B. Oxytocin
     C. Estrogen
     D. Progesterone
    
    

Correct Answer: A. Prolactin.

Prolactin is the hormone from the anterior pituitary gland that stimulates mammary gland secretion. Oxytocin, a posterior pituitary hormone, stimulates the uterine musculature to contract and causes the “let down” reflex.

Option B: Oxytocin has been best known for its roles in female reproduction. It is released in large amounts during labor, and after stimulation of the nipples. It is a facilitator for childbirth and breastfeeding. One of the oldest applications of oxytocin as a proper drug is as a therapeutic agent during labor and delivery. It is a stimulant widely employed to induce or augment labor, especially at term, when adequate oxytocin receptors are present. It is also one of the principal uterotonic drugs used to prevent postpartum hemorrhage.
Option C: Estrogen is a steroid hormone associated with the female reproductive organs and is responsible for the development of female sexual characteristics. In the uterus, estrogen helps to proliferate endometrial cells in the follicular phase of the menstrual cycle, thickening the endometrial lining in preparation for pregnancy.
Option D: Progesterone is an endogenous steroid hormone that is commonly produced by the adrenal cortex as well as the gonads, which consist of the ovaries and the testes. Progesterone is also secreted by the ovarian corpus luteum during the first ten weeks of pregnancy, followed by the placenta in the later phase of pregnancy. The conversion of progesterone generation from the corpus luteum to the placenta generally occurs after week ten.