A 23-year-old woman, gravida 1, para 0, comes to the office for a routine prenatal care visit. She is at 35 weeks gestation and feels well. She reports regular fetal movement and no contractions, loss of fluid, or vaginal bleeding. Pregnancy to date has been uncomplicated and the patient has no underlying medical conditions. She signed up for a clinical trial investigating prolactin. At 34 weeks gestation, she had a serum prolactin level several times higher than what was recorded prior to pregnancy. Which of the following hormones prevents lactation in this patient?

Question

A 23-year-old woman, gravida 1, para 0, comes to the office for a routine prenatal care visit.  She is at 35 weeks gestation and feels well.  She reports regular fetal movement and no contractions, loss of fluid, or vaginal bleeding.  Pregnancy to date has been uncomplicated and the patient has no underlying medical conditions.  She signed up for a clinical trial investigating prolactin.  At 34 weeks gestation, she had a serum prolactin level several times higher than what was recorded prior to pregnancy.  Which of the following hormones prevents lactation in this patient?

Quizplus · Accepted Answer

Eductional Objective: In pregnancy, progesterone is secreted by the corpus luteum and later by the placenta.  Although prolactin secretion increases as pregnancy progresses, high progesterone levels inhibit lactation by preventing binding of prolactin to receptors on alveolar cells in the breast.

A 23-Year-Old Woman, Gravida 1, Para 0, Comes to the Office