(M) Lec 5: Reproductive Function (Females) Flashcards
Regulation of Female Reproduction
- Each ovary has ____ million primordial follicles at birth
- Maturation is blocked until ____
- This refers to the recruitment of a few primordial follicles for maturation
- A single mature follicle is produced each normal menstrual cycle at approximately day ____
- When you run out of follicles, ____ will occur
- 2 to 4 million
- Puberty
- Puberty
- Fourteen (14)
- Menopause
Ovarian Cycle
- Refers to Day 1 to 14
- Starts with the onset of menses and ends on the day of the LH surge
- Follicular growth and development occurs
Follicular Phase
Ovarian Cycle (Follicular Phase)
- FSH stimulates ____ production which will cause a ____ feedback effect
- However upon reaching the ____, it will shift to a ____ feedback mechanism further resulting in a surge of GnRH, FSH, and LH
- If estrogen is the dominant hormone in this phase, what happens to the uterine lining?
- Estrogen; Negative
- Peak; Positive
- Cell Proliferation occurs
Ovarian Cycle (Follicular Phase)
- This is a sign that an ovum is about to be released, usually 24 hours later from this event
- If estrogen is the dominant hormone in this phase, what happens to the uterine lining?
- LH Surge
- It thickens as estrogen promotes cell proliferation
Ovarian Cycle
- Refers to Day 14 to 15
- Starts with the extrusion of an ovum (ovulation) and ends with the onset of menses
- The corpus luteum secretes progesterone, estrogen, and inhibin
- The corpus luteum eventually turns into corpus albicans which can no longer maintain the uterine lining causing it to shed
Luteal Phase
Ovarian Cycle (Luteal Phase)
- After a woman ovulates, the follicle that just released the egg turns into ____
- This is rich in ____ and a very good source of progesterone
- The function of progesterone is to influence the ____ activity of the endometrium
- TOF: Estrogen levels decrease again in this phase
- Corpus Luteum
- Cholesterol
- Secretory
- False (increase again)
Note: Progesterone also stabilizes the uterine lining, preventing menses
Ovarian Cycle
- Dominant ovarian hormone during the follicular phase?
- Dominant ovarian hormone during the luteal phase?
- Estrogen
- Progesterone
Endometrial Cycle
- Covers days 1 to 5 of menstruation and days 6 to 14 of proliferation
- Estrogen restores the endometrium via cell proliferation and growth
Proliferative Stage
Endometrial Cycle
- Refers to Day 15 to 28
- The estrogen and progesterone cause the development of numerous exocrine glands
- There is preparation of the endometrium for implantation of the embryo
- If no fertilization occurs, it will lead to the shedding of the endometrium
Secretory Stage
Ovarian Cycle
If fertilization did not occur:
1. What happens to the corpus luteum?
2. What happens to progesterone levels?
3. What happens to the uterine lining?
- Turns into corpus albicans
- Progesterone drops because the source is lost (corpus luteum)
- The lining will destabilize and slough off because of the absence of progesterone
Functions of FSH:
1. In the ovaries, it stimulates the development of ovarian ____
2. In the testes, it regulates ____
- Follicles
- Spermatogenesis
Functions of LH:
1. In the ovaries, it causes ____, formation of corpus luteum, and production of estrogen and progesterone
2. In the testes, it facilitates the production of ____
- Ovulation
- Testosterone
Ovarian Hormone Production
This is used as a substrate for hormonal production
Cholesterol
Ovarian Hormone Production
What are the 3 forms of estrogens?
- E1 - Estrone
- E2 - Estradiol
- E3 - Estriol
Ovarian Hormone Production
- An 18-carbon steroid hormone not produced by the ovaries after menopause
- Works hand in hand with progesterone for uterine growth, regulation of the mestrual cycle, and maintenance of pregnancy
Estrogen
Forms of Estrogen
- Most abundant in post-menopausal women
- Comes from the adrenal glands and is produced from the adipose cells
E1 (Estrone)
Forms of Estrogen
- The most potent/estrogenic (major estrogen)
- Most abundant in pre-menopausal women
- Synthesized from testosterone and it is what is measured during the reproductive stage
E2 (Estradiol)
Forms of Estrogen
- Seen in pregnant women as this is secreted by the placenta
- A metabolite of estradiol found in maternal urine
- A marker for Down Syndrome
E3 (Estriol)
Ovarian Hormone Production
- A 21-carbon compound produced by the lutein cells of the corpus luteum
- Facilitates the secretory activity of the endometrial glands
- Has a thermogenic effect and is dominant during the luteal phase
- If there is a deficiency of this, it could lead to a failure in implantation
Progesterone
Ovarian Hormone Production
- A 19-carbon compound produced by the ovaries (from testosterone to estradiol)
- An excess of this leads to hirsutism, loss of female characteristics, and a development of male characteristics
- Only present after menopause
Androgens
Ovarian Hormone Production
- These are produced by the ovaries which inhibit FSH production
- This enhances FSH secretion
- Inhibins A and B
- Activin
Ovarian Hormone Production
Among Inhibins A and B, which is for the corpus luteum and which is for the follicles?
- Inhibin A - corpus luteum
- Inhibin B - developing follicles
Pubertal Development in Females
- Refers to the development of breast tissue and pubic hair
- Refers to the initiation of menses (around 9-11 years old)
- Thelarche
- Menarche
Menstrual Cycle Abnormalities
- No menstruation by age 16
- An abnormal cycle for a minimum of 3 to 6 months
- Infrequent and irregular cycles greater than 35-40 days
- Uterine bleeding in excess of 7 days
- Primary amenorrhea
- Secondary amenorrhea
- Oligomenorrhea
- Menorrhagia
Tests for Amenorrhea
- This assesses estrogen status and endometrial responsiveness to progesterone
- Can be given intramuscularly either in 10mg doses for 5-10 days or just one dose of 100-200mg
- Bleeding should be monitored within 2-7 days of stopping the drug
Progestin Withdrawal Test
Tests for Amenorrhea
Progestin Withdrawal Test Results:
- This occurs due to a lack of estrogen, obstruction, primary ovarian failure, or hypothalamic-pituitary insufficiency
Absence of bleeding
Tests for Amenorrhea
Progestin Withdrawal Test Results:
- Outflow tract is intact
- There is estrogenic chronic anovulation due to excess androgens (estrogens are present but the patient cannot ovulate)
- Other causes may include adrenal tumor, hyperplasia, or hyperthecosis
Presence of bleeding
Evaluation of Ovulatory Function
TOF: Basal body temperature measurement is not reliable
True
Evaluation of Ovulatory Function
- Aka preconception test
- It is a colorimetric assay done 2-3 days before the LH surge
- Not reliable in patients who have PCOS
Urinary Ovulation Predictor Kits (for LH)
Evaluation of Ovulatory Function
- Measured on Day 21 of the menstrual cycle
- A level > 3ng/mL indicates ovulation and production of progesterone
Mid-Luteal Phase Serum Progesterone Levels
Tests for Ovarian Reserves
- This is a non-steroidal estrogen receptor modulator (blocks the hypothalamic receptors)
- It stimulates the release of FSH to recruit more follicles
- Not usually done and is replaced by estrogen testing (estradiol)
Clomid Challenge Test/Clomiphene Citrate Challenge Test
Tests for Ovarian Reserves
Clomid Challenge Test Results:
1. FSH returns to baseline
2. FSH remains high
- Normal
- Abnormal (poor ovarian reserve)
Tests for Ovarian Reserves
Anti-Mullerian Hormone Test
1. AMH levels are higher in ____ fetuses, as this prevents them from developing female reproductive organs
2. Female fetuses need a ____ amount of AMH for their development
3. In females, cells inside the ____ are the ones that produce AMH
- Male
- Small
- Follicles
Tests for Ovarian Reserves
Anti-Mullerian Hormone Test
1. Higher AMH means (more/less) eggs and a (higher/lower) ovarian reserve
2. Lower AMH means (more/less) eggs and a (higher/lower) ovarian reserve
- More; Higher
- Less; Lower
Female Reproductive Abnormalities
- Refers to ↓ estrogen and ↓ LH and FSH (gonadotropin deficiency)
- Type 1 classification according to WHO
- Examples are hypothalamic-pituitary disorders
Hypogonadotropic Hypogonadism
Hypothalamic-Pituitary Disorders
- Aka postpartum hypopituitarism
- Caused by ischemic necrosis due to blood loss and hypovolemic shock during and after childbirth
- The lack of oxygen damages the pituitary gland
Sheehan’s Syndrome
Female Reproductive Abnormalities
- A type 2 classification of amenorrhea according to WHO
- FSH and LH are normal
- Examples are PCOS, hyperthecosis, adrenal hyperplasia, and adrenal tumors
Estrogenic Chronic Anovulation
Female Reproductive Abnormalities
- A disorder involving infrequent, irregular, or prolonged menstrual periods, and often excess male hormone (androgen) levels
- LH is elevated but with normal FSH
Polycystic Ovary Syndrome
Female Reproductive Abnormalities
- Patient is of a female genotype (46,XX)
- Female pseudohermaphroditism
- They have ovaries but present with secondary sexual characteristics or external genitalia of a male
- Due to a deficiency in 21-hydroxylase
Congenital Adrenal Hyperplasia
Female Reproductive Abnormalities
- A type 3 classification according to WHO
- Characterized by ovarian failure (primary hypogonadism)
- Estrogen is ↓ but FSH and LH are ↑
Hypergonadotropic Hypogonadism
Pregnancy
- This is an LH-like hormone which increases in maternal blood
- Is synthesized and secreted by the syncytiotrophoblasts of the developing placenta
Human Chorionic Gonadotropin (hCG)
Human Chorionic Gonadotropin (hCG)
- Has the same ____ sub-unit as LH, FSH, and TSH
- The ____ sub-unit of LH and hCG are almost the same
- hCG can interact with LH ____ on luteal cells
- It prevents the ____ of corpus luteum into corpus albicans
- Alpha
- Beta
- Receptors
- Regression
Human Chorionic Gonadotropin (hCG)
- After the 1st trimester, the ____ is able to produce steroid hormones (estriol)
- Increased hCG can indicate germ cell ____ and gestational ____ disease
- Placenta
- Tumors; Trophoblastic
Pregnancy
During pregnancy:
1. Estrogen and Progesterone (increase/decrease)
2. Aside from the placenta, fetal adrenal glands and liver also contribute to ____ synthesis
- Increase
- Steroid
Pregnancy
During pregnancy, ____ assesses fetal well-being in late pregnancy and promotes uteroplacental blood flow
Estriol
Pregnancy
- This is synthesized by the placenta during the last 2 trimesters
- Is similar to PRL and GH; it has weak lactogenic and growth-promoting activities
- An insulin antagonist may play a role in maternal glucose utilization
Human Placental Lactogen (HPL)
