Chapter 16, Problem 3CT

Premenstrual syndrome (PMS) can include mood swings, fluid retention (edema), anxiety, backache and joint pain, food cravings, and other symptoms. PMS usually develops after ovulation and lasts until just before or just after menstruation begins. Although the precise cause of PMS is unknown, it seems clearly related to the cyclic production of ovarian hormones. After reviewing Figure 16.3, suggest which hormonal changes may trigger PMS.

Figure 16.3 Animated! Hormones govern the menstrual and ovarian cycles. A GnRH from the hypothalamus stimulates the anterior pituitary to secrete FSH and LH. B FSH and LH stimulate a follicle to grow, an oocyte to mature, and the ovaries to secrete progesterone and estrogens that stimulate the endometrium to rebuild. C A midcycle LH surge triggers ovulation and the formation of a corpus luteum. D Progesterone and some estrogens released by the corpus luteum maintain the endometrium, but if no pregnancy occurs, they stop being released and the corpus luteum breaks down. (© Cengage Learning)