Ovary Pathophysiology PDF

# OVARY ## I. BASIC PRINCIPLES - **A.** The functional unit of the ovary is the follicle. - **B.** A follicle consists of an oocyte surrounded by granulosa, and theca cells. - 1. LH acts on theca cells to induce androgen production. - 2. FSH stimulates granulosa cells to convert androgen t...

# OVARY ## I. BASIC PRINCIPLES - **A.** The functional unit of the ovary is the follicle. - **B.** A follicle consists of an oocyte surrounded by granulosa, and theca cells. - 1. LH acts on theca cells to induce androgen production. - 2. FSH stimulates granulosa cells to convert androgen to estradiol (drives the proliferative phase of the endometrial cycle). - 3. Estradiol surge induces an LH surge, which leads to ovulation (marking the beginning of the secretory phase of the endometrial cycle). - **C.** After ovulation, the residual follicle becomes a corpus luteum, which primarily secretes progesterone (drives the secretory phase which prepares the endometrium for a possible pregnancy). - 1. Hemorrhage into a corpus luteum can result in a hemorrhagic corpus luteal cyst, especially during early pregnancy. - **D.** Degeneration of follicles results in follicular cysts. Small numbers of follicular cysts are common in women and have no clinical significance. ## II. POLYCYSTIC OVARIAN DISEASE (PCOD) - **A.** Multiple ovarian follicular cysts due to hormone imbalance. - 1. Affects roughly 5% of women of reproductive age. - **B.** Characterized by increased LH and low FSH (LH:FSH>2) - 1. Increased LH induces excess androgen production (from theca cells) resulting in hirsutism (excess hair in a male distribution). - 2. Androgen is converted to estrone in adipose tissue. - i. Estrone feedback decreases FSH resulting in cystic degeneration of follicles. - ii. High levels of circulating estrone increase risk for endometrial carcinoma. - **C.** Classic presentation is an obese young woman with infertility, oligomenorrhea, and hirsutism. Some patients have insulin resistance and may develop type 2 diabetes mellitus 10-15 years later.