206/207: Female and Male Infertility Flashcards
How does testosterone excess affect sperm levels?
Excess testosterone → decreased sperm
- Testosterone inhibits GnRH, LH/FSH via negative feedback
- Brain sees enough testosterone, shuts down the axis
- Gonadotropins LH and FSH are needed for spermatogenesis
- Most commonly from anabolic steroids.
How does a varicocele affect sperm production?
Impairs sperm production through hyperthermia
- Varicocele causes blood to pool in the piniform plexus
- More blood = increased testicular temperature
- Disrupts the counter-current heat exchange
- -> impaired sperm production
Tx = surgical intervention or radiologic embolization
What causes Asherman’s syndrome?
Uterine scarring, usually iatrogenic
Can interfere with fertility
How does marijuana affect sperm count?
Decreased, due to suppressed LH and testosterone
How does prolactin excess affect sperm levels?
Prolactin inhibits hypothalamic GnRH secretion
- -> Decreased LH/FSH
- -> Decreased spermatogenesis
- Clinical sign is gynecomastia
What is the prevalence of infertility?
15%
What genetic testing should be ordered for men with congenital bilateral absence of the vas deferens (CBAVD)?
CFTR mutation - likely that they are a carrier
Test BOTH partners
- Even if pt with CBAVD is negative for known CFTR mutations, they may be a carrier of an unidentified mutation; need to know CFTR status of partner
- Carrier of CFTR mutation can have CBAVD without other symptoms*
Which aspect of fertility is most affected by maternal age?
Egg quality and quantity
Decreased ovarian reserve
Poor egg quality (higher risk of aneuoploidy-→ miscarriage)
Note: uterus largely unaffeted; donor eggs have the same success rate in older vs. younger uteri
Describe the clinical features of congenital bilateral absence of the vas deferens
- Missing vas deferens, distal 2/3 of epididymis, seminal vesicle
- Infertility
- Likely a carrier of CFTR mutation
- Semen sample will have low pH, low ejaculate volume, azospermia
What are the most common causes of infertility in a person with a uterus?
- Anatomic abnormality
- Uterine and/or fallopian tube
- Ovulatory dysfunction
Also aging (decreased ovarian reserve)
Define infertility
Inability to conceive after one year of unprotected intercourse
Note: For female patients 35 and older, consider intervention after 6 months without conceiving - don’t want to waste time
Which part of the hypothalamic/pituitary/gonadal axis is interrupted in hypothalamic amenorrhea?
Pulsatile GnRH secretions from the hypothalamus
This is when the body is stressed out (too much exercise, anorexia, too much work/life stress)
Remember that both absent and continuous GnRH secretions will inhibit LH/FSH secretion
What is the most effective form of male contraception?
Vasectomy (cut the vas deferens)
Pull out method and/or condoms have higher failure rates b/c may not always be properly executed (obviously)
What is the best treatment option for a woman with bilaterally blocked fallopian tubes who wishes to conceive a child?
IVF
No way for the eggs to get to the uterus/meet a sperm
Age and ovarian reserve play a role in likelihood of success
Is a vasectomy immediately effective?
NO!
- Must check to make sure ejaculate has few (<100,00) nonmotile after 4 months
- Takes time to clear all the sperm hanging out in the system
- Surgery is a failure if any motile sperm persist at >6 months; repeat procedure
How long does it take after fever for sperm levels to return to normal?
Up to 3 months
Hyperthermia messes up spermatogenesis at all stages. Have to start over and replenish
If a pt has abnormal semen results <3 months after fever, rechek later
Sperm count below ___ is an indication for karyotype testing
Sperm count below 5 million is an indication for karyotype testing
Could be Kleinfelter (47, XXY) (Small firm testes, gynecomastia, azospermia)
Or microdeletions on the y-chromosome
What is the first line treatment for ovulation induction in a patient with PCOS?
Describe the MOA
Letrozole
- Oral non-steroidal aromatase inhibitor
- Aromatase converts testosterone to estrogen
- Decreased estrogen level -> brain releases more LH/FSH
- Ovulation!
List the steps of a complete evaluation for infertility in a person with a uterus
- History
- Physical
- Assess uterine cavity
- Document tubal patency
- Confirm ovulation
- Assess ovarian reserve
Order of evaluation depends on the patient
Ex: history of PID→ more worried about tubal patency
What is the MOA of clopiphene citrate?
Selective estrogen receptor modulator (SERM)
- Blocks hypothalamic estrogen receptors
- This tricks the brain into thinking there isn’t enough estrogen
- -> Increased LH and FSH
- -> induces ovulation
What is the most common genetic caues of azoospermia?
Klinefelter syndrome (47, XXY)
How will semen differ in retrograde ejaculation vs. ejaculatory duct obstruction?
Both: Low ejaculatory volume
- Retrograde ejaculation
- Normal semen pH (≥7.2)
- Ejaculatory duct obstructions
- Acidic semen pH => seminal vesicle secretions are not getting into the ejaculate
- Seen in CBAVD (congenital bilateral absence of the vas deferens, seen in CFTR carriers)
- Prostate secretions are acidic*
- Seminal vesicle secretions are alkaline*
At what age does fertility peak in a person with a uterus?
When does it begin to significantly decline?
20-24 years old
Significant decline begins at 30-32ish
OH NOOOOOOOOO. :((
What are the downsides of injectable gonadotropins?
Increased risk of multiple pregnancies
Work too well! Ovaries likely to develop >1 follicles
BUT, are used in IVF treatments when want to harvest as many eggs as possible
What are the different treatment options for obstructive vs non-obstructive azospermia?
Obstructive: surgically correct the obstruction if feasible (sperm are there, just need the open pathway)
Nonobstructive: microTESE + IVF/ICSI (not making many sperm at all, need to find them and directly combine with eggs)
