PATHO FINAL EXAM STUDY GUIDE

Reproductive

Endometrial cycle and the occurrence of ovulation

-menstrual cycleàstarts with menarche (first menstruation) ends with menopause (cessation of menstrual flow for 1 year)

-Cycles -anovulatory at first may vary in length from 10 to 60 days or more.

-As adolescence proceeds into adulthood, regular patterns of menstruation and ovulation are established at intervals ranging from 21 to 45 days.

^-Menstruation continues to recur in a recognizable and characteristic pattern during adulthood, with the length of the menstrual cycle varying considerably among women.

• commonly accepted cycle average is 28 (27 to 30) days, with rhythmic intervals of 21 to 35 days considered normal.

-Approximately 2 to 8 years before menopause, cycles begin to lengthen again with variation related to changing hormone levels

-2 phases:

• follicular/proliferative phase (postmenstrual)

-lasts until about day 14.

• endometrium grows to form a lush lining inside of the uterus.

• GnRH, activin, and inhibin from granulosa cells cause rise in FSH levels (stimulates number of follicles)
• FSH rescues dominant ovarian follicle from apoptosis day 5-7
• Estrogen and FSH make primary follicle more sensitive to FSH
• Estrogen levels increase, FSH levels drop because of inhibin-B increase from dominant follicle
• Estrogen causes cells of endometrium to proliferate and stimulate LH production
• Surge in FSH and LH require for final follicular growth and ovulation
• Androgen enhances process of follicle atresia

• luteal/secretory phase (premenstrual)
  • this is where the body secretes the hormones estrogen and progesterone. -These hormones work together to prepare the lining of the uterus for implantation.

-lasts for 12 days

-During menstruation (menses), the functional layer of the endometrium disintegrates and is discharged through the vagina.

• The estrogen and progesterone start to decline and the endometrial lining begins to shed. This lasts for

3-5 days and the process restarts.

Menstruation is followed by the follicular/proliferative phase.

-Ovulation is the release of an ovum from a mature follicle and marks the beginning of the luteal/secretory phase of the menstrual cycle. The ovarian follicle begins its transformation into a corpus luteum hence the name luteal phase.

• Pulsatile secretion of the LH from the anterior pituitary stimulates the corpus luteum to secrete

progesterone. -This will initiate the secretory phase of endometrial development.

• Glands and blood vessels in the endometrium branch and curl through a functional layer, and the glands begin to secrete a thin glycogen-containing fluid= the secretory phase. *If conception occurs the nutrient-laden endometrium is ready for implantation.
• Release of ovum from mature follicle
• Beginning of luteal/secretory phase
• Follicle begins transformation into corpus luteum (luteal phase)
• Secretion of LH from anterior pituitary stimulate corpus luteum to secrete progesterone

• Progesterone initiates secretory phase
• Glands and blood vessels in endometrium branch secrete thin glycogen-containing fluid (secretory phase)
• If conception occurs endometrium is ready for implantation
• HCG secreted 3 days after fertilization by blastocytes and maintains corpus luteum after fertilization at

day 6-7

• HCG detected in blood/urine 8-10 days after ovulation
• Production of estrogen and progesterone continues until placenta can maintain hormonal production
• If no conception/implantation corpus luteum degenerates and ends progesterone/estrogen production
• Endometrium becomes ischemic and disintegrates (ischemic menstrual phase)
• Menstruation occurs (3-7 days)=beginning of new cycle......... Continue