What does LH do during the menstrual cycle?

What does LH do during the menstrual cycle?

• A. Stimulates ovulation by triggering LH release
• B. Completes preovulatory follicles, breaks down connective tissue of the ovarian cortex, forms corpus luteum
• C. Inhibits estrogen production
• D. Causes endometrial shedding

Answer: (B)

LH surge is the trigger for the final steps of ovulation and the start of the luteal phase. At midcycle, a spike in LH prompts the dominant follicle to rupture, releasing the oocyte. This same surge drives luteinization, transforming the ruptured follicle into the corpus luteum, which then secretes progesterone (and some estrogen) to prepare the uterus for possible implantation. The description that LH completes preovulatory follicle maturation, facilitates rupture by remodeling the follicle wall, and forms the corpus luteum aligns with what LH does during the cycle. LH does not inhibit estrogen production and is not the direct cause of endometrial shedding—that shedding results from progesterone withdrawal if pregnancy doesn’t occur.

LH surge is the trigger for the final steps of ovulation and the start of the luteal phase. At midcycle, a spike in LH prompts the dominant follicle to rupture, releasing the oocyte. This same surge drives luteinization, transforming the ruptured follicle into the corpus luteum, which then secretes progesterone (and some estrogen) to prepare the uterus for possible implantation. The description that LH completes preovulatory follicle maturation, facilitates rupture by remodeling the follicle wall, and forms the corpus luteum aligns with what LH does during the cycle. LH does not inhibit estrogen production and is not the direct cause of endometrial shedding—that shedding results from progesterone withdrawal if pregnancy doesn’t occur.