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Male Outflow Tract |
Penis
Male Outflow Tract
Case: 27 year old male with azoospermia (no sperm within the semen), a normal hormone evaluation (FSH, LH, testosterone, prolactin), a normal physical examination (degree of virilization, testicular size and scrotal contents), status post (following) Y-V urethrocystoplasty as a child for difficulty urinating.
Question: What further testing or treatments should be considered in this situation?
Answer: Retrograde ejaculation into the bladder can occur since the sperm will generally take the “path of least resistance” when moving through the vas deferens during emission.
Normally the internal urethral sphincter will be stimulated during the emission process to result in closure of the bladder neck so that the sperm moves into the posterior urethra. If there has been damage to the (alpha adrenergic) nerves that mediate bladder neck closure or if there has been damage to the bladder neck itself (via prior surgery in the area) then closure of the bladder neck may not occur and the sperm may travel into the bladder rather than into the posterior urethra during emission. Retrograde ejaculation into the bladder is common following Y-V plasties of the bladder neck (usually performed during childhood) and also occurs about 40-90% of the time after men have had a prostatectomy (either TURP or abdominal prostatectomy).
The diagnosis of retrograde ejaculation into the bladder is confirmed by assessing the urine for the presence of sperm after ejaculation. If the diagnosis is confirmed then treatment depends on the presumed cause of the problem.
Men with retrograde ejaculation secondary to nervous system problems often respond to medical management (most often imipramine hydrochloride or pseudoephedrine hydrochloride) so this is usually the initial line of treatment. If medical management fails to produce antegrade ejaculation or if the cause of the problem is more likely anatomical (from prior surgery) then collection of the sperm from the bladder may allow for its use in either inseminations or assisted fertilization.
Sperm collected from the bladder that is intended to be used for attempting fertility should be “optimized” by collecting it in a specific manner.
- The urinary pH should be alkalinized to a pH of about 8 (similar to that found in semen).
- Any infection of the bladder should also be treated prior to these procedures (to reduce the subsequent entry of bacteria into the uterus during insemination).
A treatment routine that seems to be effective is to (1) identify and treat a urinary tract infection prior to the collection of sperm from the bladder, (2) administer sodium bicarbonate (650 mg four times a day) for 1-2 days prior to the procedure (to increase the pH of the urine), (3) administer prophylactic antibiotics (cipro 500 mg every 12 hours) for two doses prior to the procedure, (4) empty the bladder with a sterile catheter and irrigate the bladder with 100 cc of “sperm washing medium” (an inert buffered balanced sterile solution that often contains human tubal fluid), (5) place about 30-50cc of sperm washing medium in the bladder and remove the catheter, (6) have the man ejaculate (into the bladder), (7) collect the post-ejaculation specimen (sperm in predominantly sperm washing medium), and (8) immediately wash the sperm sample several times prior to insemination or assisted fertilization.
Case: 24 year old male with azoospermia (no sperm within the semen), a normal hormone evaluation (FSH, LH, testosterone, prolactin), a normal physical examination (degree of virilization, testicular size and scrotal contents), and a normal testicular biopsy (at which time a normal epididymis is seen but there is bilateral absence of the vas deferens).
Question: What further testing or treatments should be considered in this situation?
Answer: Congenital bilateral absence of the vas deferens is usually due to agenesis of the Wolffian ducts (from which they differentiate) and this is most often associated with one of several possible cystic fibrosis gene mutations.
Obstruction of sperm transport from the testes to the urethra (resulting in azoospermia) can involve the vas deferens, the seminal vesicles or the epididymis. Congenital malformations of the epididymis may be associated with exposure to DES (diethylstilbesterol) in utero. Remnants (nonfunctional cysts) of the Mullerian ducts (which differentiate into the uterus and fallopian tubes if the embryo is to become a female) can obstruct the ejaculatory duct and also result in azoospermia.
If the site of an obstruction can be identified and treated surgically then the man’s reproductive potential may be restored to normal. If there is a congenital absence of “part of the plumbing” (such as with a bilateral absence of the vas deferens) then mature sperm can often be retrieved via “microscopic epididymal sperm aspiration” (MESA). This sperm can then be used with assisted fertilization or insemination (usually discouraged since there is a highly limited supply of sperm). Expert advise with an infertility specialist and an Urologist (who has special expertise in male infertility microsurgery) is useful.
Penis
Case: 29 year old G0 with a history of regular menstrual intervals every 27-28 x 7 days, a normal hormone evaluation (TSH and Prolactin concentration), a hysterosalpingogram (HSG) revealing a normal uterine cavity and bilateral tubal patency, and a husband with unproven fertility yet a normal semen analysis. A postcoital test cannot be performed since there is a history of a penile erectile dysfunction such that vaginal intercourse cannot be completed.
Question: What further testing or treatments should be considered in this situation?
Answer: Penile erection is primarily a vascular event in which blood flow into the muscles of the penis (that comprise the glans penis and surround the penile urethra) increases while venous outflow from the penis decreases. The result is engorgement of the penis (tumescence) that results in an erection.
The vascular events that result in an erection are regulated by the nervous system. “Impotence” is generally defined as the consistent inability to maintain an erection long enough to complete intercourse and ejaculation.
Impotence may be due to many different causes, including (1) disorders of the central nervous system (including emotional stress, performance anxiety, some psychiatric disorders, some chronic medical diseases involving the heart or lungs, some medications that act via the central nervous system, pituitary disorders involving prolactin or thyroid hormones), (2) spinal cord disease (including some spinal injuries especially if involving the lower segments of the spine, multiple sclerosis, tumors, spina bifida), (3) dysfunction of the autonomic nervous system (including prior pelvic surgery around the rectum or penis, diabetes mellitus, vasculitis), (4) medications that can act on the vascular system (including medication for hypertension, depression, or antihistamines), (5) peripheral vascular disease (including atherosclerotic vascular disease that obstructs flow through the iliac vessels), and (6) abnormalities of the penis itself (including anatomic abnormalities in the shape of the penis).
In some situations, a man with impotence (inability to complete vaginal intercourse) can produce a semen specimen into a container through masturbation, which can then be used for insemination. Intrauterine inseminations can often effectively bypass the reproductive problem caused by the impotence. However, an urologist or other competent physician familiar with these problems should address the desirability of an evaluation for the cause of the impotence.
Case: 35 year old G0 with a history of regular menstrual intervals every 30 x 5-6 days, a normal hormone evaluation (TSH and Prolactin concentration), an encouraging ovarian reserve (basal FSH and estradiol concentrations), a hysterosalpingogram (HSG) revealing a normal uterine cavity and bilateral tubal patency, and a husband with unproven fertility. The husband is unable to collect a sample for semen analysis despite adequate penile erection and apparent “orgasm” since “nothing comes out.”
Question: What further testing or treatments should be considered in this situation?
Answer: Disorders such as this where “nothing comes out” (with an apparently normal male orgasm) may involve dysfunctions of emission (movement of sperm into the posterior penile urethra) or ejaculation (expulsion of the sperm from the penile urethra).
Nerves originating from within the lower (thoracolumbar, T12-L2) spinal cord form into the hypogastric nerve, which is primarily responsible for stimulating contraction of the (cauda) epididymis, vas deferens and ejaculatory duct to accomplish emission.
Nerves originating from within the lower (sacral, S2-4) spinal cord form into the pudendal nerve, which is triggered in a reflex manner at emission to stimulate rhythmic contractions of the muscles comprising the glans penis (the bulbocavernosus and ischiocavernosus muscles).
Prior nerve injury is often the underlying cause of a failure of emission and ejaculation.
Treatment is most commonly initially directed at medical management (with medication like the acetylcholinesterase inhibitors, which may directly stimulate the spinal “ejaculatory center”). If medical management is ineffective then a trial of penile vibratory stimulation (a penile vibrator is applied to different areas of the penis to see whether reflex stimulation can be accomplished) may be useful (the greatest benefit appears to be with spinal cord injury patients). If the penile vibratory stimulation is ineffective then rectal probe electroejaculation is generally attempted, which is only able to accomplish emission (the semen must then be milked out of the posterior urethra).
If semen can be collected with any of these procedures, then inseminations with these samples can be performed.
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