A woman with a 2-year-old son comes to her physician because she has been unable to conceive a second child for more than a year. The woman is currently breastfeeding her son.Which of the following explains how lactation suppresses ovulation?

Lactation inhibits secretion of gonadotropin- releasing hormone

14. The correct answer is C. Lactation is maintained by prolactin secretion from the anterior pituitary. Prolactin prevents ovulation by several mechanisms. It inhibits the secretion of gonadotropin-releasing hormone (GnRH) from the hypothalamus and inhibits the action of GnRH at the anterior pituitary, thus decreasing the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Finally, it inhibits the actions of LH and FSH on the ovaries. This woman might have a better chance of becoming pregnant if she were to stop breastfeeding her son. Answer A is incorrect. Lactation and the resulting high levels of prolactin do not affect estrogens action on the ovary. Answer B is incorrect. Lactation is maintained by prolactin. It does not decrease its secretion. Answer D is incorrect. Lactation results in decreased secretion of FSH. Answer E is incorrect. Lactation does not cause sterility.