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Some strategies suggested or proposed for avoiding male infertility include the following:
- Avoiding smoking as it damages sperm DNA
- Avoiding heavy marijuana and alcohol use.
- Avoiding excessive heat to the testes.
- Maintaining optimal frequency of coital activity: sperm counts can be depressed by daily coital activity and sperm motility may be depressed by coital activity that takes place too infrequently (abstinence 10–14 days or more).
- Wearing a protective cup and jockstrap to protect the testicles, in any sport such as baseball, football, cricket, lacrosse, hockey, softball, paintball, rodeo, motorcross, wrestling, soccer, karate or other martial arts or any sport where a ball, foot, arm, knee or bat can come into contact with the groin.
- Diet: Healthy diets (i.e. the Mediterranean diet) rich in such nutrients as omega-3 fatty acids, some antioxidants and vitamins, and low in saturated fatty acids (SFAs) and trans-fatty acids (TFAs) are inversely associated with low semen quality parameters. In terms of food groups, fish, shellfish and seafood, poultry, cereals, vegetables and fruits, and low-fat dairy products have been positively related to sperm quality. However, diets rich in processed meat, soy foods, potatoes, full-fat dairy products, coffee, alcohol and sugar-sweetened beverages and sweets have been inversely associated with the quality of semen in some studies. The few studies relating male nutrient or food intake and fecundability also suggest that diets rich in red meat, processed meat, tea and caffeine are associated with a lower rate of fecundability. This association is only controversial in the case of alcohol. The potential biological mechanisms linking diet with sperm function and fertility are largely unknown and require further study.
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.
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.
The development of intracytoplasmic sperm injection made conception a possibility for patients with a variety of male infertility conditions, including globozoospermia. However, fertility rates with this approach are still low, and research is ongoing into how this can be improved.
It has been found that treating globozoospermia with ICSI along with oocyte activation by calcium ionophore (an ion carrier used to increase intracellular calcium is more likely to result in conception than ICSI alone. Another promising treatment area also looks at causing oocyte activation in conjunction with ICSI, this time using spermatic binding-proteins, phospholipase C zeta (PLCζ) and postacrosomal sheath WW domain binding protein (PAWP).
The observation has been made many times that globozoospermia arises in siblings which points towards an underlying genetic cause. Recent progress has been made into determining what genes could be implicated in this pathology, with the previously mentioned genes being found to play a role. There are more genes which have been shown to be mutated in globozoospermia in mice, but these are yet to be connected to the human disease process. Examples of these include Gopc, Hrb and Csnka2. There are thousands of genes which guide the process of spermatogenesis, and knowing how they’re involved in globozoospermia is an important current area of research.
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.
"Fertility tourism" is the practice of traveling to another country for fertility treatments. It may be regarded as a form of medical tourism. The main reasons for fertility tourism are legal regulation of the sought procedure in the home country, or lower price. In-vitro fertilization and donor insemination are major procedures involved.
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.
ICSI technique is used in case of poor semen quality, low sperm count or failed fertilization attempts during prior IVF cycles. This technique involves an injection of a single healthy sperm directly injected into mature egg. The fertilized embryo is then transferred to womb.
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].
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.
Chemotherapy poses a high risk of infertility. Chemotherapies with high risk of infertility include procarbazine and other alkylating drugs such as cyclophosphamide, ifosfamide, busulfan, melphalan, chlorambucil and chlormethine. Drugs with medium risk include doxorubicin and platinum analogs such as cisplatin and carboplatin. On the other hand, therapies with low risk of gonadotoxicity include plant derivatives such as vincristine and vinblastine, antibiotics such as bleomycin and dactinomycin and antimetabolites such as methotrexate, mercaptopurine and 5-fluorouracil.
Female infertility by chemotherapy appears to be secondary to premature ovarian failure by loss of primordial follicles. This loss is not necessarily a direct effect of the chemotherapeutic agents, but could be due to an increased rate of growth initiation to replace damaged developing follicles. Antral follicle count decreases after three series of chemotherapy, whereas follicle stimulating hormone (FSH) reaches menopausal levels after four series. Other hormonal changes in chemotherapy include decrease in inhibin B and anti-Müllerian hormone levels.
Women may choose between several methods of fertility preservation prior to chemotherapy, including cryopreservation of ovarian tissue, oocytes or embryos.
Prognosis in unexplained infertility depends on many factors, but can roughly be estimated by e.g. the
Hunault model, which takes into account female age, duration of infertility/subfertility, infertility/subfertility being primary or secondary, percentage of motile sperm and being referred by a general practitioner or gynecologist.
Twelve percent of all infertility cases are a result of a woman either being underweight or overweight. Fat cells produce estrogen, in addition to the primary sex organs. Too much body fat causes production of too much estrogen and the body begins to react as if it is on birth control, limiting the odds of getting pregnant. Too little body fat causes insufficient production of estrogen and disruption of the menstrual cycle. Both under and overweight women have irregular cycles in which ovulation does not occur or is inadequate. Proper nutrition in early life is also a major factor for later fertility.
A study in the US indicated that approximately 20% of infertile women had a past or current eating disorder, which is five times higher than the general lifetime prevalence rate.
A review from 2010 concluded that overweight and obese subfertile women have a reduced probability of successful fertility treatment and their pregnancies are associated with more complications and higher costs. In hypothetical groups of 1000 women undergoing fertility care, the study counted approximately 800 live births for normal weight and 690 live births for overweight and obese anovulatory women. For ovulatory women, the study counted approximately 700 live births for normal weight, 550 live births for overweight and 530 live births for obese women. The increase in cost per live birth in anovulatory overweight and obese women were, respectively, 54 and 100% higher than their normal weight counterparts, for ovulatory women they were 44 and 70% higher, respectively.
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.
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.
Idiopathic azoospermia is where there is no known cause of the condition. It may be a result of multiple risk factors, such as age and weight. For example, a review in 2013 came to the result that oligospermia and azoospermia are significantly associated with being overweight (odds ratio 1.1), obese (odds ratio 1.3) and morbidly obese (odds ratio 2.0), but the cause of this is unknown. The review found no significant relation between oligospermia and being underweight.
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.
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).
Between 5 and 10 percent of women with POF may become pregnant. Currently no fertility treatment has officially been found to effectively increase fertility in women with POF, and the use of donor eggs with in-vitro fertilization (IVF) and adoption are popular as a means of achieving parenthood for women with POF. Some women with POF choose to live child-free. (See impaired ovarian reserve for a summary of recent randomized clinical trials and treatment methods.)
Currently New York fertility researchers are investigating the use of a mild hormone called dehydroepiandrosterone (DHEA) in women with POF to increase spontaneous pregnancy rates. Published results from studies conducted on DHEA have indicated that DHEA may increase spontaneously conceived pregnancies, decrease spontaneous miscarriage rates and improve IVF success rates in women with POF.
Additionally, over the last five years a Greek research team has successfully implemented the use of dehydroepiandrosterone (DHEA) for the fertility treatment of women suffering with POF.The majority of the patients were referred for donor eggs or surrogacy, however after a few months of DHEA administration, some succeeded in getting pregnant through IVF, IUI, IUTPI or natural conception. Many babies have been born after treatment with DHEA.
Ovarian tissue cryopreservation can be performed on prepubertal girls at risk for premature ovarian failure, and this procedure is as feasible and safe as comparable operative procedures in children.
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.
Management of AIS is currently limited to symptomatic management; no method is currently available to correct the malfunctioning androgen receptor proteins produced by "AR" gene mutations. Areas of management include sex assignment, genitoplasty, gonadectomy in relation to tumor risk, hormone replacement therapy, genetic counseling, and psychological counseling.
Hormone replacement therapy with estrogen may be used to treat symptoms of hypoestrogenism in females with the condition. There are currently no known treatments for the infertility caused by the condition in either sex.
To some extent, it is possible to change testicular size. Short of direct injury or subjecting them to adverse conditions, e.g., higher temperature than they are normally accustomed to, they can be shrunk by competing against their intrinsic hormonal function through the use of externally administered steroidal hormones. Steroids taken for muscle enhancement (especially anabolic steroids) often have the undesired side effect of testicular shrinkage.
Similarly, stimulation of testicular functions via gonadotropic-like hormones may enlarge their size. Testes may shrink or atrophy during hormone replacement therapy or through chemical castration.
In all cases, the loss in testes volume corresponds with a loss of spermatogenesis.
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%.