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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.
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.
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.
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.
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.
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.
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].
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 has led to natural pregnancies of their partners in approximately 20% of affected men. A disadvantage is the destruction of the valves at the openings of the ejaculatory ducts into the urethra 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 partners 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 female partner.
The genetic variation is irreversible, however, individuals who want to look more masculine can take testosterone. Treating adolescents with implants of controlled release testosterone has shown good results when appropriately monitored. Hormone therapy is also useful in preventing the onset of osteoporosis.
Often individuals that have noticeable breast tissue or hypogonadism experience depression and/or social anxiety because they are outside of social norms. An academic term for this is psychosocial morbidity. At least one study indicates that planned and timed support should be provided for young men with Klinefelter syndrome to ameliorate current poor psychosocial outcomes. The surgical removal of the breasts may be considered for both the psychological reasons and to reduce the risk of breast cancer.
The use of behavioral therapy can mitigate any language disorders, difficulties at school and socialization. An approach by occupational therapy is useful in children, especially those who have dyspraxia.
Azoospermia can be classified into three major types as listed. Many conditions listed may also cause various degrees of oligospermia rather than azoospermia.
By 2010 over 100 successful pregnancies have been reported using IVF technology with surgically removed sperm material from males with Klinefelter syndrome. Microdissection testicular sperm extraction in adult men with Klinefelter syndrome reported success rates of up to 45%.
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.
Mild androgen insensitivity syndrome (MAIS) is a condition that results in a mild impairment of the cell's ability to respond to androgens. The degree of impairment is sufficient to impair spermatogenesis and / or the development of secondary sexual characteristics at puberty in males, but does not affect genital differentiation or development. Female genital and sexual development is not significantly affected by the insensitivity to androgens; as such, MAIS is only diagnosed in males. The clinical phenotype associated with MAIS is a normal male habitus with mild spermatogenic defect and / or reduced secondary terminal hair.
MAIS is one of three types of androgen insensitivity syndrome, which is divided into three categories that are differentiated by the degree of genital masculinization: complete androgen insensitivity syndrome (CAIS) is indicated when the external genitalia is that of a normal female, mild androgen insensitivity syndrome (MAIS) is indicated when the external genitalia is that of a normal male, and partial androgen insensitivity syndrome (PAIS) is indicated when the external genitalia is partially, but not fully masculinized.
Androgen insensitivity syndrome is the largest single entity that leads to 46,XY undermasculinization.
Individuals with CAVD can reproduce with the assistance of modern technology with a combination of testicular sperm extraction and intracytoplasmic sperm injection (ICSI). However, as the risk of either cystic fibrosis or renal agenesis is likely to be higher in the children, genetic counseling is generally recommended.
About 10–15% of human couples are infertile, unable to conceive. In approximately in half of these cases, the underlying cause is related to the male. The underlying causative factors in the male infertility can be attributed to environmental toxins, systemic disorders such as, hypothalamic–pituitary disease, testicular cancers and germ-cell aplasia. Genetic factors including aneuploidies and single-gene mutations are also contributed to the male infertility. Patients suffering from nonobstructive azoospermia or oligozoospermia show microdeletions in the long arm of the Y chromosome and/or chromosomal abnormalities, each with the respective frequency of 9.7% and 13%. A large percentage of human male infertility is estimated to be caused by mutations in genes involved in primary or secondary spermatogenesis and sperm quality and function. Single-gene defects are the focus of most research carried out in this field.
NR5A1 mutations are associated with male infertility, suggesting the possibility that these mutations cause the infertility. However, it is possible that these mutations individually have no major effect and only contribute to the male infertility by collaboration with other contributors such as environmental factors and other genomics variants. Vice versa, existence of the other alleles could reduce the phenotypic effects of impaired NR5A1 proteins and attenuate the expression of abnormal phenotypes and manifest male infertility solely.
Nuclear receptor subfamily 5 group A member 1 (NR5A1), also known as SF1 or Ad4BP (MIM 184757), is located on the long arm of chromosome 9 (9q33.3). The NR5A1 is an orphan nuclear receptor that was first identified following the search for a common regulator of the cytochrome P450 steroid hydroxylase enzyme family. This receptor is a pivotal transcriptional regulator of an array of genes involved in reproduction, steroidogenesis and male sexual differentiation and also plays a crucial role in adrenal gland formation in both sexes. NR5A1 regulates the mullerian inhibitory substance by binding to a conserved upstream regulatory element and directly participates in the process of mammalian sex determination through mullerian duct regression. Targeted disruption of NR5A1 (Ftzf1) in mice results in gonadal and adrenal agenesis, persistence of Mullerian structures and abnormalities of the hypothalamus and pituitary gonadotropes. Heterozygous animals demonstrate a milder phenotype including an impaired adrenal stress response and reduced testicular size. In humans, NR5A1 mutations were first described in patients with 46, XY karyotype and disorders of sex development (DSD), Mullerian structures and primary adrenal failure (MIM 612965). After that, heterozygous NR5A1 mutations were described in seven patients showing 46, XY karyotype and ambiguous genitalia, gonadal dysgenesis, but no adrenal insufficiency. Since then, studies have confirmed that mutations in NR5A1 in patients with 46, XY karyotype cause severe underandrogenisation, but no adrenal insufficiency, establishing dynamic and dosage-dependent actions for NR5A1. Subsequent studies revealed that NR5A1 heterozygous mutations cause primary ovarian insufficiency (MIM 612964).
Sertoli cell-only syndrome (a.k.a. Del Castillo syndrome and germ cell aplasia ) is a disorder characterized by male sterility without sexual abnormality. It describes a condition of the testes in which only Sertoli cells line the seminiferous tubules.
Congenital absence of the vas deferens (CAVD) is a condition in which the vasa deferentia reproductive organs, fail to form properly prior to birth. It may either be unilateral (CUAVD) or bilateral (CBAVD).
Spermatogenesis arrest is a complex process of interruption in the differentiation of germinal cells of specific cellular type, which elicits an altered spermatozoa formation. Spermatogenic arrest is usually due to genetic factors resulting in irreversible azoospermia. However some cases may be consecutive to hormonal, thermic, or toxic factors and may be reversible either spontaneously or after a specific treatment.
Microdeletions in the Y chromosome have been found at a much higher rate in infertile men than in fertile controls and the correlation found may still go up as improved genetic testing techniques for the Y chromosome are developed.
Much study has been focused upon the "azoospermia factor locus" (AZF), at Yq11. A specific partial deletion of AZFc called "gr/gr deletion" is significantly associated with male infertility among Caucasians in Europe and the Western Pacific region.
Additional genes associated with spermatogenesis in men and reduced fertility upon Y chromosome deletions include RBM, DAZ, SPGY, and TSPY.
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.
Y chromosome microdeletion is currently diagnosed by extracting DNA from leukocytes in a man's blood sample, mixing it with some of the about 300 known genetic markers for sequence-tagged sites (STS) on the Y chromosome, and then using polymerase chain reaction amplification and gel electrophoresis in order to test whether the DNA sequence corresponding to the selected markers is present in the DNA.
Such procedures can test only the integrity of a tiny part of the overall 23 million base pair long Y chromosome, therefore the sensitivity of such tests depends on the choice and number of markers used. Present diagnostic techniques can only discover certain types of deletions and mutations on a chromosome and give therefore no complete picture of genetic causes of infertility. They can only demonstrate the presence of some defects, but not the absence of any possible genetic defect on the chromosome.
The gold standard test for genetic mutation, namely complete DNA sequencing of a patient's Y chromosome, is still far too expensive for use in epidemiologic research or even clinical diagnostics.
Young's syndrome, also known as azoospermia sinopulmonary infections, sinusitis-infertility syndrome and Barry-Perkins-Young syndrome, is a rare condition that encompasses a combination of syndromes such as bronchiectasis, rhinosinusitis and reduced fertility. In individuals with this syndrome, the functioning of the lungs is usually normal but the mucus is abnormally viscous. The reduced fertility (azoospermia) is due to functional obstruction of sperm transport down the genital tract at the epididymis where the sperms are found in viscous, lipid-rich fluid. The syndrome was named after Donald Young, the urologist who first made observations of the clinical signs of the syndrome in 1972. There have been several studies undertaken suggesting that contact with mercury might cause the syndrome.
A variant of Young's syndrome has been observed in an individual, showing slightly different signs and symptoms.