A Some Menstrual Cycle Info 1 Begins at

A. Some Menstrual Cycle Info 1. Begins at puberty and ends at menopause (Menopause: estrogen production declines) 2. 28 -day cycle 3. Hormones involved: -Luteinizing Hormone (LH) -Follicle Stimulating Hormone (FSH) -Estrogen -Progesterone * See Diagram Handout

The Menstrual Cycle Follicle Phase Ovulation Menstruation Corpus Luteum Phase *FSH = Follicle Stimulating Hormone *LH = Leutinizing Hormone

The Menstrual Cycle Follicle Phase • Low levels of estrogen and progesterone cause pituitary to secrete FSH • FSH causes an egg to mature in a follicle (ovary) • Follicle secretes estrogen which causes uterine lining (endometrium) to thicken *FSH = Follicle Stimulating Hormone *LH = Leutinizing Hormone

Egg maturation in ovary

The Menstrual Cycle Ovulation • Estrogen production inhibits FSH production • Pituitary secretes LH, which causes follicle to burst and release mature egg into fallopian tube *FSH = Follicle Stimulating Hormone *LH = Leutinizing Hormone

Egg maturation in ovary

The Menstrual Cycle Corpus Luteum Phase • Burst follicle turns yellow and becomes the corpus luteum, which produces progesterone to maintain thick uterine lining • LH production decreases

The Menstrual Cycle Menstruation • If fertilization doesn’t occur, corpus luteum disintegrates • Progesterone secretion decreases, cause uterine lining to detach from uterine wall • Tissue, egg, and blood are discharged from body

The Menstrual Cycle Follicle Phase Ovulation • Low levels of estrogen and progesterone cause pituitary to secrete FSH • FSH causes an egg to mature in a follicle (ovary) • Follicle secretes estrogen which causes uterine lining (endometrium) to thicken • Estrogen production inhibits FSH production • Pituitary secretes LH, which causes follicle to burst and release mature egg into fallopian tube Menstruation Corpus Luteum Phase • If fertilization doesn’t occur, corpus luteum disintegrates • Progesterone secretion decreases, cause uterine lining to detach from uterine wall • Burst follicle turns yellow & becomes the corpus luteum, which produces progesterone to maintain thick uterine lining • Tissue, egg, and blood are discharged from body *FSH = Follicle Stimulating Hormone • LH production decreases *LH = Leutinizing Hormone