Table Of ContentGametogenesis
Gametogenesis
Jason M. Franasiak, M.D.
Resident Physician
University of North Carolina
OOBB0011-- 1
Spermatogenesis
Spermatogenesis
(23, 1n) Spermatozoa
(23, 1n) Spermatids
Meiosis II
Secondary
(23, 2n)
spermatocytes
Meiosis I
Primary
(46, 4n)
spermatocytes
(46, 2n) Spermatogonia
Kaplan Anatomy: Figure I-10-2
FA 2012: 532.1 • FA 2011: 480.1 • FA 2010: 478 • OB01- 2
ME 3e: 400
Spermatozoa
Spermatozoa
Spermatozoa:
75 days for production
- 2/3 time in seminiferous tubules
- 1/3 time in epididymus
Normal for fertility:
Semen volume: 2-5 ml
Total sperm number: > 20 million
Progressive motility: > 50%
Kaplan Anatomy: Figure I-10-4
FA 2012: n/a • FA 2011: 479.3 • FA 2010: 477 • OB01- 3
ME 3e: 400
Hormonal control of testes
Hormonal control of testes
Kaplan Anatomy 2011: Figure X-10-1
FA 2012: 534.1 • FA 2011: 481.2 • FA 2010: 479 • OB01- 4
ME 3e: 401
Oogenesis
Oogenesis
Secondary
Primary Oocyte Ovum
Oogonium Oocyte
2n 4n 4n 2n N
Replication
!"#$%&
&'"()*+&
Prophase I Metaphase II
Arrest Arrest
(until ovulation) (until fertilization)
FA 2012: 537.1 • FA 2011: 484.2 • FA 2010: 482 • OB01- 5
ME 3e: 404
Folliculogenesis
Folliculogenesis
Kaplan Anatomy: Figure I-11-2
FA 2012: 536.1 • FA 2011: 483.2 • FA 2010: 481 • OB01- 6
ME 3e: 404
Menstrual cycle
Menstrual cycle
Chris, commons.wikimedia.org.
Used with permission.
FA 2012: 536.1 • FA 2011: 483.2 • FA 2010: 481 • OB01- 7
ME 3e: 405
Menses
Menses
Kaplan Physiology: Figure X-11-4
FA 2012: 536.1 • FA 2011: 483.2 • FA 2010: 481 • OB01- 8
ME 3e: 406
Follicular phase
Follicular phase
Kaplan Physiology: Figure X-11-1
FA 2012: 536.1 • FA 2011: 483.2 • FA 2010: 481 • OB01- 9
ME 3e: 406
Ovulation
Ovulation
Kaplan Physiology: Figure X-11-2
FA 2012: 536.1 • FA 2011: 483.2 • FA 2010: 481 • OB01- 10
ME 3e: 406
Luteal phase
Luteal phase
Ed Uthman, commons.wikimedia.org.
Kaplan Physiology: Figure X-11-3
Used with permission.
FA 2012: 536.1 • FA 2011: 483.2 • FA 2010: 481 • OB01- 11
ME 3e: 406
Polycystic ovarian syndrome
Polycystic ovarian syndrome/disease (PCOS)
! LH
! androgen (testosterone) synthesis by theca cells
"! FSH
•! Young females with obesity, amenorrhea, and anovulation
•! Hirsutism and acne (due to ! testosterone)
•! Bilateral cystic ovaries (multiple immature follicles)
•! Sometimes ! estrogen
FA 2012: 545.1 • FA 2011: 490.1 • FA 2010: OB01- 12
• ME 3e: 414
Uterine cycle
Uterine cycle
Menses Proliferative Secretory Chris, commons.wikimedia.org.
Used with permission.
FA 2012: 536.1 • FA 2011: 483.2 • FA 2010: 481 • OB01- 13
ME 3e: 405
GnRH Release
GnRH
• Synthesized in preoptic nucleus of hypothalamus
!
• Pulsatile secretion
!
• Continuous application leads to downregulation of
!
GnRH receptors in the anterior pituitary
• GnRH agonists (e.g. leuprolide)
!
•! pulsatile - treat infertility by inducing ovulation
•! continuous - " estrogen to treat endometriosis, fibroids
FA 2012: 553.1 • FA 2011: 497.1 • FA 2010: 495 • OB01- 14
ME 3e: 403
Menopause
Menopause
•! Abrupt decrease in estrogen in aging women
•! Due to loss of ovarian follicles with time
•! Average age of onset: 52 years
•! Progressive increase in LH/FSH (loss of inhibitory feedback)
FA 2012: 538.2 • FA 2011: 485.2 • FA 2010: 483 • OB01- 15
ME 3e: 403
Anovulation
Possible causes of anovulation
•! Menopause
•! Premature ovarian failure
•! PCOS (obesity and estrogen excess)
•! Asherman syndrome (uterine adhesions, scar tissue)
•! Hyperprolactinemia, thyroid disease
•! Eating disorders, excessive exercise
•! (Rarely) Cushing’s syndrome
FA 2012: 544.5 • FA 2011: 489.6 • FA 2010: 487 • OB01- 16
ME 3e: 403
Menopause symptoms
Menopause symptoms
• Vaginal dryness
!
• Thermoregulatory dysfunction – “hot flashes”
!
(first 5 years after onset)
• Night sweats
!
• Loss of bone density -
!
(begins at age 30, accelerates 5-7 years after menopause)
Symptoms alleviated by hormone replacement therapy
BUT:
•! Increased risk of clot formation, stroke, breast cancer
•! Progesterone must be given with estrogen to prevent
uterine cancer
FA 2012: 538.2 • FA 2011: 485.2 • FA 2010: 483 • OB01- 17
ME 3e: 410
Fertilization and Embryogenesis
Fertilization and Embryogenesis
Jason M. Franasiak, M.D.
Resident Physician
University of North Carolina
OOBB0022-- 1
Fertilization and week 1
Fertilization and week 1
Kaplan Anatomy: Figure II-2-1
FA 2012: 124.2 • FA 2011: 118.2 • FA 2010: 118 • OB02- 2
ME 3e: 142
