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Administration of luteinizing hormone (LH) (or human chorionic gonadotropin) and follicle-stimulating hormone (FSH) is very effective in the treatment of male infertility due to hypogonadotropic hypogonadism. Although controversial, off-label clomiphene citrate, an antiestrogen, may also be effective by elevating gonadotropin levels.
Though androgens are absolutely essential for spermatogenesis and therefore male fertility, exogenous testosterone therapy has been found to be ineffective in benefiting men with low sperm count. This is thought to be because very high local levels of testosterone in the testes (concentrations in the seminiferous tubules are 20- to 100-fold greater than circulating levels) are required to mediate spermatogenesis, and exogenous testosterone therapy (which is administered systemically) cannot achieve these required high local concentrations (at least not without extremely supraphysiological dosages). Moreover, exogenous androgen therapy can actually impair or abolish male fertility by suppressing gonadotropin secretion from the pituitary gland, as seen in users of androgens/anabolic steroids (who often have partially or completely suppressed sperm production). This is because suppression of gonadotropin levels results in decreased testicular androgen production (causing diminished local concentrations in the testes) and because FSH is independently critical for spermatogenesis. In contrast to FSH, LH has little role in male fertility outside of inducing gonadal testosterone production.
Estrogen, at some concentration, has been found to be essential for male fertility/spermatogenesis. However, estrogen levels that are too high can impair male fertility by suppressing gonadotropin secretion and thereby diminishing intratesticular androgen levels. As such, clomiphene citrate (an antiestrogen) and aromatase inhibitors such as testolactone or anastrozole have shown effectiveness in benefiting spermatogenesis.
Low-dose estrogen and testosterone combination therapy may improve sperm count and motility in some men, including in men with severe oligospermia.
Treatments vary according to the underlying disease and the degree of the impairment of the male fertility. Further, in an infertility situation, the fertility of the female needs to be considered.
Pre-testicular conditions can often be addressed by medical means or interventions.
Testicular-based male infertility tends to be resistant to medication. Usual approaches include using the sperm for intrauterine insemination (IUI), in vitro fertilization (IVF), or IVF with intracytoplasmatic sperm injection (ICSI). With IVF-ICSI even with a few sperm pregnancies can be achieved.
Obstructive causes of post-testicular infertility can be overcome with either surgery or IVF-ICSI. Ejaculatory factors may be treatable by medication, or by IUI therapy or IVF.
Vitamin E helps counter oxidative stress, which is associated with sperm DNA damage and reduced sperm motility. A hormone-antioxidant combination may improve sperm count and motility. However there is only some low quality evidence from few small studies that oral antioxidants given to males in couples undergoing in vitro fertilisation for male factor or unexplained subfertility result in higher live birth rate. It is unclear if there are any adverse effects.
Treatment takes place within the context of infertility management and needs also to consider the fecundity of the female partner. Thus the choices can be complex.
In a number of situations direct medical or surgical intervention can improve the sperm concentration, examples are use of FSH in men with pituitary hypogonadism, antibiotics in case of infections, or operative corrections of a hydrocele, varicocele, or vas deferens obstruction.
In most cases of oligospermia including its idiopathic form there is no direct medical or surgical intervention agreed to be effective. Empirically many medical approaches have been tried including clomiphene citrate, tamoxifen, HMG, FSH, HCG, testosterone, Vitamin E, Vitamin C, anti-oxidants, carnitine, acetyl-L-carnitine, zinc, high-protein diets. In a number of pilot studies some positive results have been obtained. Clomiphene citrate has been used with modest success. The combination of tamoxifen plus testosterone was reported to improve the sperm situation.
The use of carnitine showed some promise in a controlled trial in selected cases of male infertility improving sperm quality and further studies are needed.
In many situations, intrauterine inseminations are performed with success. In more severe cases IVF, or IVF - ICSI is done and is often the best option, specifically if time is a factor or fertility problems coexist on the female side.
The Low dose Estrogen Testosterone Combination Therapy may improve sperm count and motility in some men including severe oligospermia.
Pre- and post-testicular azoospermia are frequently correctible, while testicular azoospermia is usually permanent. In the former the cause of the azoospermia needs to be considered and it opens up possibilities to manage this situation directly. Thus men with azoospermia due to hyperprolactinemia may resume sperm production after treatment of hyperprolactinemia or men whose sperm production is suppressed by exogenous androgens are expected to produce sperm after cessation of androgen intake. In situations where the testes are normal but unstimulated, gonadotropin therapy can be expected to induce sperm production.
A major advancement in recent years has been the introduction of IVF with ICSI which allows successful fertilization even with immature sperm or sperm obtained directly from testicular tissue. IVF-ICSI allows for pregnancy in couples where the man has irreversible testicular azoospermia as long as it is possible to recover sperm material from the testes. Thus men with non-mosaic Klinefelter's syndrome have fathered children using IVF-ICSI. Pregnancies have been achieved in situations where azoospermia was associated with cryptorchism and sperm where obtained by testicular sperm extraction (TESE).
In men with posttesticular azoospermia a number of approaches are available. For obstructive azoospermia IVF-ICSI or surgery can be used and individual factors need to be considered for the choice of treatment. Medication may be helpful for retrograde ejaculation.
Achieving a pregnancy naturally may be a challenge if the male suffers from a low sperm count. However, chances are good if the female partner is fertile; many couples with this problem have been successful. Prognosis is more limited if there is a combination of factors that include sperm dysfunction and reduced ovarian reserve.
Research into globozoospermia is aimed at improving understanding of its cause and developing treatment options.
Treatment depends on the cause of infertility, but may include counselling, fertility treatments, which include in vitro fertilization. According to ESHRE recommendations, couples with an estimated live birth rate of 40% or higher per year are encouraged to continue aiming for a spontaneous pregnancy. Treatment methods for infertility may be grouped as medical or complementary and alternative treatments. Some methods may be used in concert with other methods. Drugs used for both women and men include clomiphene citrate, human menopausal gonadotropin (hMG), follicle-stimulating hormone (FSH), human chorionic gonadotropin (hCG), gonadotropin-releasing hormone (GnRH) analogues, aromatase inhibitors, and metformin.
Medical treatment of infertility generally involves the use of fertility medication, medical device, surgery, or a combination of the following. If the sperm are of good quality and the mechanics of the woman's reproductive structures are good (patent fallopian tubes, no adhesions or scarring), a course of ovarian stimulating medication maybe used. The physician or WHNP may also suggest using a conception cap cervical cap, which the patient uses at home by placing the sperm inside the cap and putting the conception device on the cervix, or intrauterine insemination (IUI), in which the doctor or WHNP introduces sperm into the uterus during ovulation, via a catheter. In these methods, fertilization occurs inside the body.
If conservative medical treatments fail to achieve a full term pregnancy, the physician or WHNP may suggest the patient undergo in vitro fertilization (IVF). IVF and related techniques (ICSI, ZIFT, GIFT) are called assisted reproductive technology (ART) techniques.
ART techniques generally start with stimulating the ovaries to increase egg production. After stimulation, the physician surgically extracts one or more eggs from the ovary, and unites them with sperm in a laboratory setting, with the intent of producing one or more embryos. Fertilization takes place outside the body, and the fertilized egg is reinserted into the woman's reproductive tract, in a procedure called embryo transfer.
Other medical techniques are e.g. tuboplasty, assisted hatching, and Preimplantation genetic diagnosis.
Testosterone has been used to successfully treat undervirilization in some but not all men with PAIS, despite having supraphysiological levels of testosterone to start with. Treatment options include transdermal gels or patches, oral or injectable testosterone undecanoate, other injectable testosterone esters, testosterone pellets, or buccal testosterone systems. Supraphysiological doses may be required to achieve the desired physiological effect, which may be difficult to achieve using non-injectable testosterone preparations. Exogenous testosterone supplementation in unaffected men can produce various unwanted side effects, including prostatic hypertrophy, polycythemia, gynecomastia, hair loss, acne, and the suppression of the hypothalamic-pituitary-gonadal axis, resulting in the reduction of gonadotropins (i.e., luteinizing hormone and follicle-stimulating hormone) and spermatogenic defect. These effects may not manifest at all in men with AIS, or might only manifest at a much higher concentration of testosterone, depending on the degree of androgen insensitivity. Those undergoing high dose androgen therapy should be monitored for safety and efficacy of treatment, possibly including regular breast and prostate examinations. Some individuals with PAIS have a sufficiently high sperm count to father children; at least one case report has been published that describes fertile men who fit the criteria for grade 2 PAIS (micropenis, penile hypospadias, and gynecomastia). Several publications have indicated that testosterone treatment can correct low sperm counts in men with MAIS. At least one case report has been published that documents the efficacy of treating a low sperm-count with tamoxifen in an individual with PAIS.
The aim for hormone replacement therapy (HRT) for both men and women is to ensure that the level of circulating hormones (testosterone for men and oestrogen/progesterone for women) is at the normal physiological level for the age of the patient. At first the treatment will produce most of the physical and psychological changes seen at puberty, with the major exception that there will be no testicular development in men and no ovulation in women.
After the optimum physical development has been reached HRT for men will continue to ensure that the normal androgen function is maintained; such as libido, muscle development, energy levels, hair growth, and sexual function. In women, a variety of types of HRT will either give a menstruation cycle or not as preferred by the patient. HRT is very important in both men and women to maintain bone density and to reduce the risk of early onset osteoporosis.
The fertility treatments used for both men and women would still include hormone replacement in their action.
There are a range of different preparations available for HRT for both men and women; a lot of these, especially those for women are the same used for standard HRT protocols used when hormone levels fall in later life or after the menopause.
For males with KS / CHH the types of delivery method available include daily patches, daily gel use, daily capsules, sub cutaneous or intramuscular injections or six monthly implants. Different formulations of testosterone are used to ensure both the anabolic and androgenic effects of testosterone are achieved.
Testosterone undecanoate is commonly used worldwide, though less so in the US, for treating male KS / CHH patients and has proved to be effective in maintaining good testosterone levels with an increased injection period of up to 12 weeks.
The precise treatment method used and interval between injections will vary from patient to patient and may need to be adjusted to maintain a physiological normal level of testosterone over a longer period of time to prevent the mood swings or adverse effects that can occur if testosterone levels are too high or low. Some treatments may work better with some patients than others so it might be a case of personal choice as which one to use.
As an alternative human chorionic gonadotrophin (hCG) can also be used to stimulate natural testosterone production. It acts in the same way as LH; stimulating the Leydig cells in the testes to produce testosterone. hCG can be used as pre-cursor to male fertility treatments but it can be used in isolation just for testosterone production.
There are no specialist HRT treatments available just for women with KS/HH but there are multitude of different HRT products on the market including oral contraceptives and standard post-menopause products. Pills are popular but patches are also available. It may take some trial and error to find the appropriate HRT for the patient depending on how her body reacts to the particular HRT. Specialist medical advice will be required to ensure the correct levels of oestrogen and progesterone are maintained each month, depending on whether the patient requires continuous HRT (no-bleed) or a withdrawal option to create a "menstrual" type bleed. This withdrawal bleed can be monthly or over longer time periods depending on the type of medication used.
Fertility treatments for people with KS/HH will require specialist advice from doctors experienced in reproductive endocrinology. There is a good success rate for achieving fertility for patients with KS/HH, with some experts quoting up to a 70% success rate, if IVF techniques are used as well. However, there are factors that can have a negative effect on fertility and specialist advice will be required to determine if these treatments are likely to be successful.
Fertility treatments involve the administration of the gonadotropins LH and FSH in order to stimulate the production and release of eggs and sperm. Women with KS or HH have an advantage over the men as their ovaries normally contain a normal number of eggs and it sometimes only takes a few months of treatment to achieve fertility while it can take males up to two years of treatment to achieve fertility.
A new potential new form of fertility treatment underwent clinical trials in 2013 and 2014 by Merck Sharp & Dohme. The trial evaluated a longer acting form of FSH, in the form of corifollitropin alfa. Injections were taken fortnightly instead of the normal twice weekly it is hoped that this would induce sperm production within months rather than the two years it can take with currently available medications.
Human chorionic gonadotrophin (hCG) is sometimes used to stimulate testosterone production in men and ovulation induction in women. For men it acts in the same way as LH; stimulating the Leydig cells in the testes to produce testosterone. Common trade names for hCG products include Pregnyl, Follutein, Profasi, or Choragon. Some men with KS or HH take hCG solely for testosterone production.
Human menopausal gonadotrophin (hMG) is used to stimulate sperm production in men and for multiple egg production and ovulation induction in women. It contains a mixture of both LH and FSH. In men the FSH acts on the sperm producing Sertoli cells in the testes. This can lead to testicular enlargement but can take anything from 6 months to 2 years for an adequate level of sperm production to be achieved. Common trade names for hMG products include Menopur, Menogon, Repronex, or Pergonal.
Purified forms of FSH are also available and are sometimes used with hCG instead of using hMG.
Females with KS / HH would normally require both hCG and FSH in order to achieve fertility. Other cases of female infertility can be treated with just FSH but females (and most males) with KS / CHH would require the use of both forms of gonadotropin injection.
Injections can be intramuscular but are normally taken just underneath the skin (subcutaneous) and are normally taken two or three times a week.
For both men and women, an alternative method (but not widely available), is the use of an infusion pump to provide GnRH (or LHRH) in pulsatile doses throughout the day. This stimulates the pituitary gland to release natural LH and FSH in order to activate testes or ovaries. The use of Kisspeptin delivered in the same pulsatile manner is also under evaluation as a possible treatment for fertility induction.
Due to its mild presentation, MAIS often goes unnoticed and untreated. Management of MAIS is currently limited to symptomatic management; methods to correct a malfunctioning androgen receptor protein that result from an AR gene mutation are not currently available. Treatment includes surgical correction of mild gynecomastia, minor hypospadias repair, and testosterone supplementation. Supraphysiological doses of testosterone have been shown to correct diminished secondary sexual characteristics in men with MAIS, as well as to reverse infertility due to low sperm count. As is the case with PAIS, men with MAIS will experience side effects from androgen therapy (such as the suppression of the hypothalamic-pituitary-gonadal axis) at a higher dosage than unaffected men. Careful monitoring is required to ensure the safety and efficacy of treatment. Regular breast and prostate examinations may be necessary due to comorbid association with breast and prostate cancers.
The presence of round headed sperm in a semen analysis sample confirms the diagnosis of globozoospermia. The lack of acrosome can be ascertained by a technique known as immunofluorescence.
Until 1995, the only options for people with globozoospermia who wished to conceive were adoption or sperm donation. With the advancement of assisted reproductive techniques (ART) it is now possible for those with globozoospermia to conceive using their own sperm. The main technique used is intracytoplasmic sperm injection (ICSI) where fertilisation is achieved by a single sperm being injected into the egg. Some studies have shown it is possible for a viable embryo to be created with this technique alone, however others have found it necessary to also use calcium ionophore treatment for fertilisation to be successful. Calcium ionophore treatment is used to artificially activate the oocyte. This treatment may be necessary as globozoospermic sperm can be less likely to activate the oocyte, an important stage in fertilisation.
The treatment options currently available focus on overcoming the prognosis of infertility which is associated with globozoospermia. So far there are no treatment options to prevent or cure globozoospermia.
Genitoplasty, unlike gender assignment, can be irreversible, and there is no guarantee that adult gender identity will develop as assigned despite surgical intervention. Some aspects of genitoplasty are still being debated; a variety of different opinions have been presented by professionals, self-help groups, and patients over the last few decades. Points of consideration include what conditions justify genitoplasty, the extent and type of genitoplasty that should be employed, when genitoplasty should be performed, and what the goals of genitoplasty should be. Gender assignment itself does not predicate the need for immediate genitoplasty; in some cases, surgical intervention can be delayed to allow the affected child to reach an age and maturity sufficient to have a role in such decisions. Some studies suggest that early surgeries can still produce satisfactory outcomes, while others suggest it to be unlikely. Even surgeries that are planned as one-stage procedures often require further major surgery. Scarring and tissue loss that result from repeated surgical procedures are of particular concern, due to the presumed negative impact on sexual function.
While it is thought that feminizing genitoplasty typically requires fewer surgeries to achieve an acceptable result and results in fewer urologic difficulties, there is no evidence that feminizing surgery results in a better psychosocial outcome. In one study, individuals with grade 3 PAIS who were raised male rated their body image and sexual function similarly to those who were raised female, even though they were more likely to have genitalia that were abnormal in size and appearance; more than half of the male participants had a stretched penile length that was below 2.5 standard deviations of the mean, while only 6% of female participants presented with a short vagina in adulthood, and participating physicians gave a lower cosmetic rating to the surgical results of the men than the women. Both male and female participants cited the appearance of their genitalia as being the greatest contributing factor to their dissatisfaction with their body image. In two larger studies, the common predictor of gender reassignment was stigmatization related to having an intersex condition.
The outcome of masculinizing genitoplasty is dependent on the amount of erectile tissue and the extent of hypospadias. Procedures include correction of penile curvature and chordee, reconstruction of the urethra, hypospadias correction, orchidopexy, and Müllerian remnant removal to prevent infection and pseudo-incontinence. Erectile prosthesis may be inserted in cases of successful neophalloplasty in adulthood, although it has a high morbidity. Additional surgeries may be required to correct postsurgical complications such as stenosis of the anastomosis between the native urethra and the graft, urethral fistulas, and posterior displacement of the balanic meatus. Successful masculinizing genitoplasty performed on individuals with grade 3 PAIS often requires multiple surgeries.
If feminizing genitoplasty is performed in infancy, the result will need to be refined at puberty through additional surgery. Procedures include clitoral reduction / recession, labiaplasty, repair of the common urogenital sinus, vaginoplasty, and vaginal dilation through non-surgical pressure methods. Clitoral reduction / recession surgery carries with it the risk of necrosis as well as the risk of impairing the sexual function of the genitalia, and thus should not be performed for less severe clitoromegaly. Clitoral surgery should be focused on function rather than appearance, with care being taken to spare the erectile function and innervation of the clitoris. If PAIS presents with a common urogenital sinus, the American Academy of Pediatrics currently recommends that surgery to separate the urethra from the vagina be performed at an early age. As is the case for CAIS, vaginal dilation using pressure dilation methods should be attempted before the surgical creation of a neovagina is considered, and neither should be performed before puberty. Complications of feminizing genitoplasty can include vaginal stenosis, meatal stenosis, vaginourethral fistula, female hypospadias, urinary tract injuries, and recurrent clitoromegaly. Successful feminizing genitoplasty performed on individuals with grade 3 PAIS often requires multiple surgeries, although more surgeries are typically required for successful masculinizing genitoplasty in this population.
Many surgical procedures have been developed to create a neovagina, as none of them is ideal. Surgical intervention should be considered only after non-surgical pressure dilation methods have failed to produce a satisfactory result. Neovaginoplasty can be performed using skin grafts, a segment of bowel, ileum, peritoneum, , buccal mucosa, amnion, or dura mater. Success of such methods should be determined by sexual function, and not by vaginal length alone, as has been done in the past. Ileal or cecal segments may be problematic because of a shorter mesentery, which may produce tension on the neovagina, leading to stenosis. The sigmoid neovagina is thought to be self-lubricating, without the excess mucus production associated with segments of small bowel. Vaginoplasty may create scarring at the introitus (the vaginal opening), requiring additional surgery to correct. Vaginal dilators are required postoperatively to prevent vaginal stenosis from scarring. Other complications include bladder and bowel injuries. Yearly exams are required, as neovaginoplasty carries a risk of carcinoma, although carcinoma of the neovagina is uncommon. Neither neovaginoplasty nor vaginal dilation should be performed before puberty.
There are no treatments which increase prolactin levels in humans. Treatment differs based on the reason for diagnosis. Women who are diagnosed with hypoprolactinemia following lactation failure are typically advised to formula feed, although treatment with metoclopramide has been shown to increase milk supply in clinical studies. For subfertility, treatment may include clomiphene citrate or gonadotropins.
Several treatments have been found to be effective in managing AES, including aromatase inhibitors and gonadotropin-releasing hormone analogues in both sexes, androgen replacement therapy with non-aromatizable androgens such as DHT in males, and progestogens (which, by virtue of their antigonadotropic properties at high doses, suppress estrogen levels) in females. In addition, male patients often seek bilateral mastectomy, whereas females may opt for breast reduction if warranted.
Medical treatment of AES is not absolutely necessary, but it is recommended as the condition, if left untreated, may lead to excessively large breasts (which may necessitate surgical reduction), problems with fertility, and an increased risk of endometriosis and estrogen-dependent cancers such as breast and endometrial cancers later in life. At least one case of male breast cancer has been reported.
Potential methods in unexplained infertility include oral ovarian stimulation agents (such as clomifene citrate, anastrozole or letrozole) as well as intrauterine insemination (IUI), intracervical insemination (ICI) and in vitro fertilization (IVF).
In women who have not had previous treatment, ovarian stimulation combined with IUI achieves approximately the same live birth rate as IVF. On the other hand, in women who have had previous unsuccessful treatment, IVF achieves a live birth rate approximately 2-3 times greater than ovarian stimulation combined with IUI.
IUI and ICI has higher pregnancy rates when combined with ovarian stimulation in couples with unexplained infertility, for IUI being 13% unstimulated and 15% stimulated, and for ICI being 8% unstimulated and 15% stimulated. However, the rate of twin birth increases substantially with IUI or ICI combined with ovarian stimulation, for IUI being 6% unstimulated and 23% stimulated, and for ICI being 6% unstimulated and 23% stimulated.
According to NICE guidelines, oral ovarian stimulation agents should not be given to women with unexplained infertility. Rather, it is recommended that in vitro fertilization should be offered to women with unexplained infertility when they have not conceived after 2 years of regular unprotected sexual intercourse. IVF avails for embryo transfer of the appropriate number of embryos to give good chances of pregnancy with minimal risk of multiple birth.
A review of randomized studies came to the result that IVF in couples with a high chance of natural conception, as compared to IUI/ICI with or without ovarian stimulation, was "more" effective in three studies and "less" effective in two studies.
There is no evidence for an increased risk of ovarian hyperstimulation syndrome (OHSS) with IVF when compared with ovarian stimulation combined with IUI.
The presence of abnormally-shaped sperm can negatively affect fertility by preventing transport through the cervix and/or preventing sperm from adhering to the ovum. Achieving a pregnancy may be difficult.
In testing for teratozoospermia, sperm are collected, stained and analyzed under a microscope to detect abnormalities. These abnormalities may include heads that are large, small, tapered, or pyriform or tails that are abnormally shaped.
Antiestrogens have been shown to be effective in the treatment of teratozoospermia.
Teratozoospermia (including the "globozoospermia" type), may be treated by intracytoplasmic sperm injection (ICSI), injecting sperm directly into the egg. Once the egg is fertilized, abnormal sperm morphology does not appear to influence blastocyst development or blastocyst morphology. Even with severe teratozoospermia, microscopy can still detect the few sperm cells that have a "normal" morphology, allowing for optimal success rate.
Sertoli cell only syndrome is like other non-obstructive azoospermia (NOA) cases are managed by sperm retrieval through testicular sperm extraction (mTESE), micro-surgical testicular sperm extraction (mTESE), or testicular biopsy. On retrieval of viable sperm this could be used in Intracytoplasmic Sperm injection ICSI
In 1979, Levin described germinal cell aplasia with focal spermatogenesis where a variable percentage of seminiferous tubules contain germ cells. It is important to discriminate between both in view of ICSI.
A retrospective analysis performed in 2015 detailed the outcomes of N=148 men with non-obstructive azoospermia and diagnosed Sertoli cell-only syndrome:
- Men with SCOS: 148
- Testicular sperm was successfully retrieved: 35/148
- Successful ICSI: 20/148
- Clinical pregnancy: 4/148
This study considers the effect of FSH levels on clinical success, and it excludes abnormal karyotypes. All patients underwent MD-TESE in Iran. Ethnicity and genetic lineage may have an impact on treatment of azoospermia [citation needed].
The treatment depends on the cause. Medications may work for retrograde ejaculation but only in a few cases. Surgery rarely is the first option for retrograde ejaculation and the results have proven to be inconsistent. Medications do not help retrograde ejaculation if there has been permanent damage to the prostate or the testes from radiation. Medications also do not help if prostate surgery has resulted in damage to the muscles or nerves. Medications only work if there has been mild nerve damage caused by diabetes, multiple sclerosis or mild spinal cord injury.
These medications tighten the bladder neck muscles and prevent semen from going backwards into the bladder. However, the medications do have many side effects and they have to be taken at least 1–2 hours prior to sexual intercourse. In many cases, the medications fail to work at the right time because most men are not able to predict when they will have an orgasm.
Aspermia is the complete lack of semen with ejaculation (not to be confused with azoospermia, the lack of sperm cells in the semen). It is associated with infertility.
One of the causes of aspermia is retrograde ejaculation, which can be brought on by excessive drug use, or as a result of prostate surgery. It can also be caused by alpha blockers such as tamsulosin and silodosin.
Another cause of aspermia is ejaculatory duct obstruction, which may result in a complete lack of or a very low-concentration semen (oligospermia), in which the semen contains only the secretion of accessory prostate glands downstream to the orifice of the ejaculatory ducts.
Aspermia can be caused by androgen deficiency. This can be the result of absence of puberty, in which the prostate gland and seminal vesicles (which are the main sources of semen) remain small due to lack of androgen exposure and do not produce seminal fluid, or of treatment for prostate cancer, such as maximal androgen blockade.
Azoospermia can be classified into three major types as listed. Many conditions listed may also cause various degrees of oligospermia rather than azoospermia.
Sperm DNA fragmentation level is higher in men with sperm motility defects (asthenozoospermia) than in men with oligozoospermia or teratozoospermia. Among men with asthenozoospermia, 31% were found to have high levels of DNA fragmentation. As reviewed by Wright et al., high levels of DNA fragmentation have been shown to be a robust indicator of male infertility.
Asthenozoospermia (or asthenospermia) is the medical term for reduced sperm motility. Complete asthenozoospermia, that is, 100% immotile spermatozoa in the ejaculate, is reported at a frequency of 1 of 5000 men. Causes of complete asthenozoospermia include metabolic deficiencies, ultrastructural abnormalities of the sperm flagellum (see Primary ciliary dyskinesia) and necrozoospermia.
It decreases the sperm quality and is therefore one of the major causes of infertility or reduced fertility in men. A method to increase the chance of pregnancy is ICSI. The percentage of viable spermatozoa in complete asthenozoospermia varies between 0 and 100%.