Ejaculatory duct obstruction
Encyclopedia
Ejaculatory duct obstruction (EDO) is a congenital or acquired pathological condition which is characterized by the obstruction of one or both ejaculatory ducts. Thus, the efflux of (most constituents of) semen
is not possible.
It is a cause of male infertility
and / or pelvic pain. Ejaculatory duct obstruction must not be confused with an obstruction of the vas deferens
.
due to aspermia
/azoospermia
. They will suffer from a very low volume of semen
which lacks the gel-like fluid of the seminal vesicles or from no semen at all while they are able to have the sensation of an orgasm
during which they will have involuntary contractions of the pelvic musculature. This is contrary to some other forms of anejaculation
.
Ejaculatory duct obstruction is the underlying cause for 1 - 5 % of male infertility
.
In addition, it is reported to be a cause for pelvic pain, especially shortly after ejaculation
. In case of proven fertility but unresolved pelvic pain, even one or both partially obstructed ejaculatory ducts may be the origin of pelvic pain and oligospermia
.
Ejaculatory duct obstruction may result in a complete lack of semen
(aspermia
) or a very low-volume semen (oligospermia
) which may contain only the secretion of accessory prostate glands downstream to the orifice of the ejaculatory ducts.
In addition to the congenital form which is often caused by cysts of the müllerian duct
the obstruction can be acquired due to an inflammation caused by chlamydia, prostatitis
, tuberculosis
of the prostate and other pathogens. In Addition, calculus (medicine)
was reported to mechanically block the ejaculatory duct, leading to infertility. However, in many patients, there is no history of an inflammation and the underlying cause simply remains unknown.
(oligospermia
) or no semen at all (dry ejaculation/aspermia
) are a logical consequence of an obstruction downstream of the seminal vesicles which contribute most to the volume of the semen. Usually, men will be able to observe a runny/fluid, low-volume semen
by themselves during masturbation
. Since the seminal vesicles contain a viscous, alkaline fluid rich in fructose, a chemical analysis of the semen
of affected men will result in a low concentration of fructose
and a low pH
. A microscopic semen analysis
will reveal aspermia
/azoospermia
.
In contrast, if both vasa deferentia are obstructed (which may be the result of intended sterilization), a semen analysis
will also reveal aspermia
/azoospermia
, but an almost normal volume of the semen
, since the efflux of the seminal vesicles is not hindered. This is because approx. 80% of the volume of the semen
is the gel-like fluid originating from the seminal vesicles whereas the fraction from the testicles / epididymis
, which contains the spermatozoa accounts for only 5-10% of the volume of the semen
. In addition, if an obstruction of the vasa deferentia is the cause for the azoospermia, the concentration of fructose
in the semen will also be normal, since the fructose comes primarily from the fluid stored in the seminal vesicles. If the seminal-vesicles contain spermatozoa, but the semen does not, the obstruction must be downstream of the seminal vesicles and the ejaculatory ducts are very likely to be obstructed, provided that other causes for a dry ejaculation/aspermia
such as an retrograde ejaculation
are ruled out.
Attempts are sometimes made to diagnose an ejaculatory duct obstruction by means of medical imaging, e.g. transrectal ultrasound
or MRI, transrectal needle-aspiration of the seminal-vesicles However transrectal ultrasound has a relatively low sensitivity
of approx. 50 % and thus is only a tool to rule-out cyst
s in the region of the orifices but is not sufficient to rule out an obstruction of the ejaculatory ducts due to other causes. In approx. 50 % of cases of unexplained low-volume azoospermia MRI and TRUS do not reveal any pathological findings, because it is difficult to see alterations in a narrowed, scarred duct with these methods. Due to the blockage of ejaculatory ducts, enlarged seminal vesicles are frequently seen in patients with ejaculatory duct obstructions. However, this is again neither a proof of an obstruction nor do normal-sized seminal vesicles rule-out an obstruction of the ejaculatory ducts.
Since ejaculatory duct obstruction is a relatively rare cause of infertility, this possibility may be unfamiliar to some physicians, even some urologists.
such that urine
may flow backwards into the seminal vesicles.
Another, experimental approach is the recanalization of the ejaculatory ducts by transrectal or transurethral inserted balloon catheter
Though much less invasive and preserving the anatomy of the ejaculatory ducts, this procedure is probably not completely free of complications either and success-rates are unknown. There is a clinical study currently ongoing to examine the success-rate of recanalization of the ejaculatory ducts by means of balloon dilation.
Usually, affected men have a normal production of spermatozoa in their testicles, so that after spermatozoa were harvested directly from the testes e.g. by TESE, or the seminal vesicles (by needle aspiration) they and their partner are potentially candidates for some treatment-options of assisted reproduction e.g. in-vitro fertilisation. Note that in this case, most of the treatment (e.g. ovarian stimulation
and transvaginal oocyte retrieval
) is transferred to the probably healthy wife/girlfriend.
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
is not possible.
It is a cause of male infertility
Male infertility
Male infertility refers to the inability of a male to achieve a pregnancy in a fertile female. In humans it accounts for 40-50% of infertility. Male infertility is commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity.-Pre-testicular...
and / or pelvic pain. Ejaculatory duct obstruction must not be confused with an obstruction of the vas deferens
Vas deferens
The vas deferens , also called ductus deferens, , is part of the male anatomy of many vertebrates; they transport sperm from the epididymis in anticipation of ejaculation....
.
Prevalence, etiology and symptoms
If both ejaculatory ducts are completely obstructed, affected men will demonstrate male infertilityMale infertility
Male infertility refers to the inability of a male to achieve a pregnancy in a fertile female. In humans it accounts for 40-50% of infertility. Male infertility is commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity.-Pre-testicular...
due to aspermia
Aspermia
Aspermia is the complete lack of semen . Naturally, it is associated with infertility....
/azoospermia
Azoospermia
Azoospermia is the medical condition of a male not having any measurable level of sperm in his semen. It is associated with very low levels of fertility or even sterility, but many forms are amenable to medical treatment...
. They will suffer from a very low volume of semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
which lacks the gel-like fluid of the seminal vesicles or from no semen at all while they are able to have the sensation of an orgasm
Orgasm
Orgasm is the peak of the plateau phase of the sexual response cycle, characterized by an intense sensation of pleasure...
during which they will have involuntary contractions of the pelvic musculature. This is contrary to some other forms of anejaculation
Anejaculation
Anejaculation is the pathological inability to ejaculate in males, with or without orgasm.It can depend on one or more of several causes, including ':*Sexual inhibition*Pharmacological inhibition...
.
Ejaculatory duct obstruction is the underlying cause for 1 - 5 % of male infertility
Male infertility
Male infertility refers to the inability of a male to achieve a pregnancy in a fertile female. In humans it accounts for 40-50% of infertility. Male infertility is commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity.-Pre-testicular...
.
In addition, it is reported to be a cause for pelvic pain, especially shortly after ejaculation
Ejaculation
Ejaculation is the ejecting of semen from the male reproductory tract, and is usually accompanied by orgasm. It is usually the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. In rare cases ejaculation occurs because of prostatic disease...
. In case of proven fertility but unresolved pelvic pain, even one or both partially obstructed ejaculatory ducts may be the origin of pelvic pain and oligospermia
Oligospermia
Oligospermia, also oligozoospermia, refers to semen with a low concentration of sperm and is a common finding in male infertility. Often semen with a decreased sperm concentration may also show significant abnormalities in sperm morphology and motility...
.
Ejaculatory duct obstruction may result in a complete lack of semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
(aspermia
Aspermia
Aspermia is the complete lack of semen . Naturally, it is associated with infertility....
) or a very low-volume semen (oligospermia
Oligospermia
Oligospermia, also oligozoospermia, refers to semen with a low concentration of sperm and is a common finding in male infertility. Often semen with a decreased sperm concentration may also show significant abnormalities in sperm morphology and motility...
) which may contain only the secretion of accessory prostate glands downstream to the orifice of the ejaculatory ducts.
In addition to the congenital form which is often caused by cysts of the müllerian duct
Müllerian duct
Müllerian ducts are paired ducts of the embryo that run down the lateral sides of the urogenital ridge and terminate at the Müllerian eminence in the primitive urogenital sinus. In the female, they will develop to form the Fallopian tubes, uterus, cervix, and the upper two-third of the vagina; in...
the obstruction can be acquired due to an inflammation caused by chlamydia, prostatitis
Prostatitis
Prostatitis is an inflammation of the prostate gland, in men. A prostatitis diagnosis is assigned at 8% of all urologist and 1% of all primary care physician visits in the United States.-Classification:...
, tuberculosis
Tuberculosis
Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
of the prostate and other pathogens. In Addition, calculus (medicine)
Calculus (medicine)
A calculus is a stone that forms in an organ or duct of the body. Formation of calculi is known as lithiasis...
was reported to mechanically block the ejaculatory duct, leading to infertility. However, in many patients, there is no history of an inflammation and the underlying cause simply remains unknown.
Diagnosis
Low-volume, runny/fluid semenSemen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
(oligospermia
Oligospermia
Oligospermia, also oligozoospermia, refers to semen with a low concentration of sperm and is a common finding in male infertility. Often semen with a decreased sperm concentration may also show significant abnormalities in sperm morphology and motility...
) or no semen at all (dry ejaculation/aspermia
Aspermia
Aspermia is the complete lack of semen . Naturally, it is associated with infertility....
) are a logical consequence of an obstruction downstream of the seminal vesicles which contribute most to the volume of the semen. Usually, men will be able to observe a runny/fluid, low-volume semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
by themselves during masturbation
Masturbation
Masturbation refers to sexual stimulation of a person's own genitals, usually to the point of orgasm. The stimulation can be performed manually, by use of objects or tools, or by some combination of these methods. Masturbation is a common form of autoeroticism...
. Since the seminal vesicles contain a viscous, alkaline fluid rich in fructose, a chemical analysis of the semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
of affected men will result in a low concentration of fructose
Fructose
Fructose, or fruit sugar, is a simple monosaccharide found in many plants. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into the bloodstream during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847...
and a low pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
. A microscopic semen analysis
Semen analysis
A semen analysis evaluates certain characteristics of a male's semen and the sperm contained in the semen. It may be done while investigating a couple's infertility or after a vasectomy to verify that the procedure was successful. It is also used for testing donors for sperm donation, in stud...
will reveal aspermia
Aspermia
Aspermia is the complete lack of semen . Naturally, it is associated with infertility....
/azoospermia
Azoospermia
Azoospermia is the medical condition of a male not having any measurable level of sperm in his semen. It is associated with very low levels of fertility or even sterility, but many forms are amenable to medical treatment...
.
In contrast, if both vasa deferentia are obstructed (which may be the result of intended sterilization), a semen analysis
Semen analysis
A semen analysis evaluates certain characteristics of a male's semen and the sperm contained in the semen. It may be done while investigating a couple's infertility or after a vasectomy to verify that the procedure was successful. It is also used for testing donors for sperm donation, in stud...
will also reveal aspermia
Aspermia
Aspermia is the complete lack of semen . Naturally, it is associated with infertility....
/azoospermia
Azoospermia
Azoospermia is the medical condition of a male not having any measurable level of sperm in his semen. It is associated with very low levels of fertility or even sterility, but many forms are amenable to medical treatment...
, but an almost normal volume of the semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
, since the efflux of the seminal vesicles is not hindered. This is because approx. 80% of the volume of the semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
is the gel-like fluid originating from the seminal vesicles whereas the fraction from the testicles / epididymis
Epididymis
The epididymis is part of the male reproductive system and is present in all male amniotes. It is a narrow, tightly-coiled tube connecting the efferent ducts from the rear of each testicle to its vas deferens. A similar, but probably non-homologous, structure is found in cartilaginous...
, which contains the spermatozoa accounts for only 5-10% of the volume of the semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
. In addition, if an obstruction of the vasa deferentia is the cause for the azoospermia, the concentration of fructose
Fructose
Fructose, or fruit sugar, is a simple monosaccharide found in many plants. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into the bloodstream during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847...
in the semen will also be normal, since the fructose comes primarily from the fluid stored in the seminal vesicles. If the seminal-vesicles contain spermatozoa, but the semen does not, the obstruction must be downstream of the seminal vesicles and the ejaculatory ducts are very likely to be obstructed, provided that other causes for a dry ejaculation/aspermia
Aspermia
Aspermia is the complete lack of semen . Naturally, it is associated with infertility....
such as an retrograde ejaculation
Retrograde ejaculation
In the human male reproductive system, retrograde ejaculation occurs when semen, which would normally be ejaculated via the urethra, is redirected to the urinary bladder. Normally, the sphincter of the bladder contracts before ejaculation forcing the semen to exit via the urethra, the path of least...
are ruled out.
Attempts are sometimes made to diagnose an ejaculatory duct obstruction by means of medical imaging, e.g. transrectal ultrasound
Ultrasound
Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is...
or MRI, transrectal needle-aspiration of the seminal-vesicles However transrectal ultrasound has a relatively low sensitivity
Sensitivity and specificity
Sensitivity and specificity are statistical measures of the performance of a binary classification test, also known in statistics as classification function. Sensitivity measures the proportion of actual positives which are correctly identified as such Sensitivity and specificity are statistical...
of approx. 50 % and thus is only a tool to rule-out cyst
Cyst
A cyst is a closed sac, having a distinct membrane and division on the nearby tissue. It may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, a cyst could go away on its own or may have to be removed through surgery.- Locations :* Acne...
s in the region of the orifices but is not sufficient to rule out an obstruction of the ejaculatory ducts due to other causes. In approx. 50 % of cases of unexplained low-volume azoospermia MRI and TRUS do not reveal any pathological findings, because it is difficult to see alterations in a narrowed, scarred duct with these methods. Due to the blockage of ejaculatory ducts, enlarged seminal vesicles are frequently seen in patients with ejaculatory duct obstructions. However, this is again neither a proof of an obstruction nor do normal-sized seminal vesicles rule-out an obstruction of the ejaculatory ducts.
Since ejaculatory duct obstruction is a relatively rare cause of infertility, this possibility may be unfamiliar to some physicians, even some urologists.
Treatment
A method to treat ejaculatory duct obstruction is transurethral resection of the ejaculatory ducts (TURED). This operative procedure is relatively invasive, has some severe complications and led to natural pregnancies in approx. 20 % of affected men. A disadvantage is the destruction of the valves at the openings of the ejaculatory ducts into the urethraUrethra
In anatomy, the urethra is a tube that connects the urinary bladder to the genitals for the removal of fluids out of the body. In males, the urethra travels through the penis, and carries semen as well as urine...
such that urine
Urine
Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...
may flow backwards into the seminal vesicles.
Another, experimental approach is the recanalization of the ejaculatory ducts by transrectal or transurethral inserted balloon catheter
Balloon catheter
A balloon catheter is a type of "soft" catheter with an inflatable "balloon" at its tip which is used during a catheterization procedure to enlarge a narrow opening or passage within the body...
Though much less invasive and preserving the anatomy of the ejaculatory ducts, this procedure is probably not completely free of complications either and success-rates are unknown. There is a clinical study currently ongoing to examine the success-rate of recanalization of the ejaculatory ducts by means of balloon dilation.
Usually, affected men have a normal production of spermatozoa in their testicles, so that after spermatozoa were harvested directly from the testes e.g. by TESE, or the seminal vesicles (by needle aspiration) they and their partner are potentially candidates for some treatment-options of assisted reproduction e.g. in-vitro fertilisation. Note that in this case, most of the treatment (e.g. ovarian stimulation
Ovarian stimulation
Ovarian hyperstimulation is where a regimen of fertility medications are used to stimulate the development of multiple follicles of the ovaries in one single cycle, resulting in superovulation . It may be used as a part of in vitro fertilization...
and transvaginal oocyte retrieval
Transvaginal oocyte retrieval
Transvaginal oocyte retrieval , also referred to as oocyte retrieval or even simply egg collection, is a technique used in in vitro fertilization in order to remove oocytes from the ovary of the female, enabling fertilization outside the body...
) is transferred to the probably healthy wife/girlfriend.