Lecture on Female Reproductive Cycle

Overview of Female Reproductive Cycle Phases

1. Menstrual Cycle

   • Duration: First 5 days of the cycle
   • Variation: Individual differences among women

2. Pre-ovulatory Phase

   • Duration: Day 6 to 13
   • Ovarian Activity: Follicular phase
   • Uterine Activity: Proliferative phase

3. Ovulation

   • Duration: Approximately 2 days
   • Process: Release of the egg

4. Post-ovulatory Phase

   • Duration: About 2 weeks
   • Ovarian Activity: Luteal phase
   • Uterine Activity: Secretory phase

Hormonal Activities and Changes

• Estrogen Secretion: Begins as 20 follicles develop and fill with fluid from granulosa cells.
• Progesterone Decline: Causes spiral arteries to constrict, leading to tissue dying and stratum functionalist to slough off.

Follicular Development

• Primary follicle develops into a secondary follicle.
• Dominant follicle increases estrogen production, developing into a mature follicle.
• Increased estrogen triggers luteinizing hormone (LH) secretion.
• Endometrial repair thickens stratum functionalis.

Ovulation Process

• Rupture of the follicle, releasing secondary oocyte into the pelvic cavity.
• Fimbriae of fallopian tubes attempt to coax oocyte into the tube.
• Surge of LH results in ovulation.
• Ovulation can be detected by changes in cervical mucus and basal body temperature.

Post-Ovulatory Phase

• Corpus Hemorrhagicum is absorbed and becomes corpus luteum under LH influence.
• Corpus luteum secretes estrogen and progesterone.
• If no fertilization, corpus albicans forms and hormone levels drop.
• If fertilization occurs, embryo secretes hCG to maintain corpus luteum.

Pregnancy and Hormonal Changes

• hCG is tested for in early pregnancy tests.
• Placenta eventually takes over hormone production.
• Estrogen and progesterone maintain pregnancy and initiate breast development for lactation.

Menstrual Abnormalities

1. Amenorrhea: Absence of menstruation caused by hormonal imbalances, weight issues, and intense athletic training.

   • Female Athlete Triad: Amenorrhea, disordered eating, and premature osteoporosis.

2. Dysmenorrhea: Severe menstrual pain due to tumors, cysts, endometriosis.

3. Abnormal Uterine Bleeding: Excessive or intermenstrual bleeding due to fibroids or hormonal imbalances.

Fibroids

• Benign tumors in the uterine wall causing pain and irregular bleeding.
• May lead to abdominal bloating.

Polycystic Ovary Syndrome (PCOS)

• Numerous cysts in ovaries from non-maturing follicles.
• Can cause infertility and increased risk of diabetes, heart issues.
• Associated with excess androgens causing hirsutism and acne.

Teratomas

• Tumors with various tissue types.
• Typically benign but immature forms can be malignant.
• Often found in ovaries or testes.

Goals for Lecture

• Understand effects of hormones in uterine/ovarian cycles.
• List and describe the four phases of the female reproductive cycle.
• Define key terms: amenorrhea, dysmenorrhea, fibroids, polycystic ovary syndrome, and teratoma.