Term
| what stimulates LH and FSH? |
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Definition
| GnRH (or LHRH) - comes from the hypothalamus and stimulates the anterior pituitary |
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Term
| where does LH come from? what cells does it stimulate? what inhibits it? |
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Definition
| LH is pulsatile and comes from the anterior pituitary. LH stimulates the leydig cells to make testosterone. (L->leydig). thus testosterone is a negative feedback inhibitor for LH. |
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Term
| what cells does FSH stimulate and where is it produced? what inhibits it? |
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Definition
| FSH comes from the anterior pituitary and stimulates the sertoli cells to initiate spermatogenesis. (fSh->Sertoli->Spermatogenesis). inhibin inhibits FSH. |
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Term
| what does prolactin inhibit? |
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Definition
| GnRH - thus hyperhyperprolactinemia produces hypogonadotropic hypogonadism |
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Term
| where is testosterone produced? is it pulsatile? |
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Definition
| in the leydig cells. testosterone is pulsatile and is highest in the AM. |
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Term
| what form is testosterone in peripheral circulation? |
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Definition
| mostly bound (to sex hormone binding globulin or albumin), but a small % is free. free testosterone is the most available, followed by that bound to albumin, and finally that bound to sex hormone globulin. (therefore it is important to examine total testosterone and % free testosterone) |
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Term
| what happens if 5 alpha reduces testosterone to DHT? |
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Definition
| DHT has 10x more affinity for receptor than testosterone. testosterone can also be aromatized to estradiol. |
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Term
| what happens in spermatogenesis? |
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Definition
| the spermatogonia (stem cell) becomes a spermatocyte (haploid) via meiosis, which then becomes a spermatid which has an acrosome, tail (9 paired microtubules), and is protected by a blood-testes barrier (prevents anti-sperm antibodies from forming - if injured as in testicular torsion, infertility may result) |
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Term
| how long does spermatogenesis take? |
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Definition
| ~3-4 months and is highly sensitive to environmental factors |
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Term
| what happens in the epididymis? |
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Definition
| the spermatozoa are stored in the epididymus where they mature in the cauda. this is important in vasovasostomy, where 5 yrs or less after a vasectomy there is a 90% chance of fertility, 5-10 yrs after there is a 70-80% chance of fertility, and >10 yrs there is <60% of fertility. |
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Term
| what is the function of the vas deferens? |
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Definition
|
|
Term
| what is the function of the seminal vesicles? |
|
Definition
| formation of coagulum for the sperm to swim in |
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|
Term
| what is the function of the prostate? |
|
Definition
| production of proteases for liquefaction |
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Term
| what are the neurologic innervations involved in male sexual function? |
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Definition
| point and shoot (parasympathetics for erection and sympathetic for emission and ejaculation) |
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Term
| how long can sperm survive in the female? |
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Definition
|
|
Term
| what is the post-coital test? |
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Definition
| a test to evaluate patients for cervical mucus, anti-sperm antibodies (usually done by gyn or endocrinologist/fertility specialist) |
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|
Term
|
Definition
| a change in the lipid membrane, allowing the acrosome to fuse to the female ovum |
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|
Term
| what is the humster test? |
|
Definition
| measurement of sperm penetration in hamster eggs |
|
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Term
| what are important questions to ask in the hx in terms of infertility? |
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Definition
| duration of infertility and other treatments. occurrence of pregnancies w/past or present partners. hx of bladder/pelvic/retroperitoneal sx (possible retrograde ejaculation due to disruption of autonomics esp w/lymph node removal). use of lubricants (some may have spermacides). DM/MS. childhood illnesses (mumps orchitis, trauma, delayed/incomplete puberty, cryptorchicism). CA tx. hx of herniorrhaphy (pediatric hernia repair). immotile cilia syndrome. inflammatory process. any viral infections or febrile illnesses. |
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Term
| what disease is congenital absence of the vas deferens seen in? |
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Definition
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|
Term
| what are some things to specifically look for on physical exam when dealing with an infertile male pt? |
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Definition
| r/o signs of hypogonadism/gynecomastia, r/o presence of testicular atrophy, evaluate the prostate, the penis (r/o hypospadius), epidydimis, the vas deferens (absent in CF), the spermatic cords (r/o varicocele), and r/o ejaculatory duct obstruction |
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Term
| what lab diagnostics are run for infertile male pts? |
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Definition
| *urinalysis (r/o hematuria and pyuria). *semen analysis (use 2 separate specimens w/48-72 hrs abstinence prior), check volume, sperm density, motility, forward progression, and morphology. *r/o leukocytes (can be mistaken for sperm). hormonal evaluation: check FSH, LH, prolactin, testosterone |
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|
Term
| *what is normal sperm concentration? |
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Definition
|
|
Term
| *what is a normal total sperm count? |
|
Definition
|
|
Term
| *what is normal sperm motility? |
|
Definition
| >50% forward progression or >25% rapid progression |
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|
Term
|
Definition
| sperm density <50 million total |
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|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| dead or immotile sperm identified |
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|
Term
|
Definition
| defects in morphology (most common) |
|
|
Term
|
Definition
| live sperm seen in a centrifuged pellet, but not in regular analysis |
|
|
Term
| what are things to test in terms of abnormalities of seminal fluid? |
|
Definition
| *quantitation of leukocytes in semen (difficult to distinguish from immature, round germ cells - use monoclonal assay). *antisperm antibody testing: immunobead test (ASA should be suspected if clumping, agglutination, poor post-coital test or diminished motility - may occur if blood-testis barrier is breached) |
|
|
Term
| what are things to test in terms of abnormalities of sperm function? |
|
Definition
| *sperm capacitation assays (capacitation: the hyperactive motility with cellular changes before the spermatozoa can bind to the zona pellucida and undergo the acrosome reaction). *humster test (timed test of sperm penetration of hamster eggs - good predictor for IVF potential) |
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|
Term
| what are some genetic considerations in terms of male infertility? |
|
Definition
| *13% of men w/obstructed azoospermia and 6% of men w/severe oligospermia have microdeletions of the Y chromosome. *klinefelter's syndrome (XXY) is found in 4-10% of men w/non-obstructive azoospermia. *cystic fibrosis (CFTR gene) can lead to the bilateral absence of the vas deferens. |
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Term
|
Definition
| a dilation (varicosity) of the internal spermatic vein - the most common surgically correctable cause of male infertility (33%). |
|
|
Term
| why are 90% of varicoceles located on the L side? |
|
Definition
| the L spermatic vein drains into the L renal vein at an acute angle |
|
|
Term
| what will a sperm test show for pts with a varicocele? |
|
Definition
| a "stress pattern" - decreased concentration, motility, and morphology of sperm. when fixed, 50-90% show improved semen analysis but only 30-50% pregnancy rates. |
|
|
Term
| what are other evaluations available for infertile male pts? |
|
Definition
| testicular bx (done generally with severe oligospermia or azoospeermia), vasography, trans-rectal ultrasound to look at seminal vesicle, seminal fructose (check for obstruction), and post-coital analysis (see if there is a problem w/ejaculation - possible neurologic defect if lots of sperm in urine) |
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|
Term
| what is tx for hyperprolactinemia? |
|
Definition
|
|
Term
| what is tx for kallmann's syndrome? |
|
Definition
| gonadotropin (hCG) followed by hMG (perogonal) |
|
|
Term
| what is tx for antisperm antibodies? |
|
Definition
|
|
Term
| what is tx for retrograde ejaculation? |
|
Definition
| antihistamine (pseudoephedrines to tighten up bladder neck) and alpha stimulation |
|
|
Term
| what is tx for CAH (congenital adrenal hyperplasia)? |
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Definition
|
|
Term
| what are some empiric treatments (no discernible etiology) used for male infertility? |
|
Definition
| anti-estrogens (clomiphene, tamoxifen), hCG/hMG injections, GnRH/LHRH, kallikrien, and testosterone rebound (give high testosterone and cut it off to cause testicles to rebound and improve output) |
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|
Term
| what are assisted reproductive techniques? |
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Definition
| the next step when varicocele sx and empiric therapy have failed: semen processing, intrauterine insemination, in vitro fertilization, gamete intra-fallopian transfer, microsurgical epididymal sperm aspiration, testicular sperm extraction, and intracytoplasmic sperm injection. |
|
|
Term
| what is semen processing? |
|
Definition
| sperm washing, percoll gradients, and swim ups. Y sperm swim faster than X sperm and in europe you can choose which you want. |
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|
Term
| what is intrauterine insemination? |
|
Definition
| processed sperm are instilled via a small catheter into the uterus |
|
|
Term
| what is in vitro fertilization? |
|
Definition
| the embryo is implanted directly into the uterus - very expensive |
|
|
Term
| what is gamete intra-fallopian transfer (GIFT)? |
|
Definition
| retrieved oocytes and sperm are placed together in fallopian tubes prior to fertilization - cheaper b/c not making an embryo |
|
|
Term
| what is microsurgical epididymal sperm aspiration (MESA)? |
|
Definition
| this or testicular sperm extraction (TESE) is for vasectomy pts or those missing a vas deferens (CF) - sperm are taken from the epididymis and then given directly to the lab for GIFT or IVF (no increased risk of congenital malformations) |
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|
Term
| what are some ethical dilemmas associated with fertility medicine? |
|
Definition
| sex can be determined at the 8 cell stage, therefore sex selection is possible. stem cell research also allows for transplant of testicular stem cells to repopulate and restore fertility. |
|
|
Term
| what is ICSI (intracytoplasmic sperm injection)? |
|
Definition
| the best sperm (or spermatocyte) from a sample is taken and directly injected into the egg for fertilization. this is better than any other male infertility treatment b/c it addresses any and all male infertility factors. |
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