Ovulation is triggered by a surge in which hormone?

Ovulation is triggered by a surge in which hormone?

• A. FSH
• B. LH
• C. Estrogen
• D. Progesterone

Answer: (B)

The key idea is that ovulation is driven by a surge of luteinizing hormone (LH) from the anterior pituitary. Midway through the cycle, rising estrogen from the dominant follicle provides positive feedback to the hypothalamus and pituitary, triggering a sharp increase in LH release. That LH surge acts on the follicle to induce its rupture and release the oocyte. LH also promotes meiosis completion in the oocyte and the formation of the corpus luteum afterward. FSH helps recruit and grow follicles but does not trigger ovulation by itself, estrogen’s role is to cause the LH surge, and progesterone rises after ovulation rather than triggering it.

The key idea is that ovulation is driven by a surge of luteinizing hormone (LH) from the anterior pituitary. Midway through the cycle, rising estrogen from the dominant follicle provides positive feedback to the hypothalamus and pituitary, triggering a sharp increase in LH release. That LH surge acts on the follicle to induce its rupture and release the oocyte. LH also promotes meiosis completion in the oocyte and the formation of the corpus luteum afterward. FSH helps recruit and grow follicles but does not trigger ovulation by itself, estrogen’s role is to cause the LH surge, and progesterone rises after ovulation rather than triggering it.