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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.
Most cases of vaginal hypoplasia associated with CAIS can be corrected using non-surgical pressure methods. The elastic nature of vaginal tissue, as demonstrated by its ability to accommodate the differences in size between a tampon, a penis, and a baby's head, make dilation possible even in cases when the vaginal depth is significantly compromised. Treatment compliance is thought to be critical to achieve satisfactory results. Dilation can also be achieved via the Vecchietti procedure, which stretches vaginal tissues into a functional vagina using a traction device that is anchored to the abdominal wall, subperitoneal sutures, and a mold that is placed against the vaginal dimple. Vaginal stretching occurs by increasing the tension on the sutures, which is performed daily. The non-operative pressure dilation method is currently recommended as the first choice, since it is non-invasive, and highly successful. Vaginal dilation should not be performed before puberty.
While it is recommended that women with CAIS eventually undergo gonadectomy to mitigate cancer risk, there are differing opinions regarding the necessity and timing of gonadectomy. The risk of malignant germ cell tumors in women with CAIS increases with age and has been estimated to be 3.6% at 25 years and 33% at 50 years. However, only three cases of malignant germ cell tumors in prepubescent girls with CAIS have been reported in the last 100 years. The youngest of these girls was 14 years old. If gonadectomy is performed early, then puberty must be artificially induced using gradually increasing doses of estrogen. If gonadectomy is performed late, then puberty will occur on its own, due to the aromatization of testosterone into estrogen. At least one organization, the Australasian Paediatric Endocrine Group, classifies the cancer risk associated with CAIS as low enough to recommend against gonadectomy, although it warns that the cancer risk is still elevated above the general population, and that ongoing cancer monitoring is essential. Some choose to perform gonadectomy if and when inguinal hernia presents. Estrogen replacement therapy is critical to minimize bone mineral density deficiencies later in life.
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.
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.
The primary management of cryptorchidism is watchful waiting, due to the high likelihood of self-resolution. Where this fails, a surgery, called orchiopexy, is effective if inguinal testes have not descended after 4–6 months. Surgery is often performed by a pediatric urologist or pediatric surgeon, but in many communities still by a general urologist or surgeon.
When the undescended testis is in the inguinal canal, hormonal therapy is sometimes attempted and very occasionally successful. The most commonly used hormone therapy is human chorionic gonadotropin (HCG). A series of hCG injections (10 injections over 5 weeks is common) is given and the status of the testis/testes is reassessed at the end. Although many trials have been published, the reported success rates range widely, from roughly 5 to 50%, probably reflecting the varying criteria for distinguishing retractile testes from low inguinal testes. Hormone treatment does have the occasional incidental benefits of allowing confirmation of Leydig cell responsiveness (proven by a rise of the testosterone by the end of the injections) or inducing additional growth of a small penis (via the testosterone rise). Some surgeons have reported facilitation of surgery, perhaps by enhancing the size, vascularity, or healing of the tissue. A newer hormonal intervention used in Europe is the use of GnRH analogs such as nafarelin or buserelin; the success rates and putative mechanism of action are similar to hCG, but some surgeons have combined the two treatments and reported higher descent rates. Limited evidence suggests that germ cell count is slightly better after hormone treatment; whether this translates into better sperm counts and fertility rates at maturity has not been established. The cost of either type of hormone treatment is less than that of surgery and the chance of complications at appropriate doses is minimal. Nevertheless, despite the potential advantages of a trial of hormonal therapy, many surgeons do not consider the success rates high enough to be worth the trouble since the surgery itself is usually simple and uncomplicated.
In cases where the testes are identified preoperatively in the inguinal canal, orchiopexy is often performed as an outpatient and has a very low complication rate. An incision is made over the inguinal canal. The testis with accompanying cord structure and blood supply is exposed, partially separated from the surrounding tissues ("mobilized"), and brought into the scrotum. It is sutured to the scrotal tissue or enclosed in a "subdartos pouch." The associated passage back into the inguinal canal, an inguinal hernia, is closed to prevent re-ascent.
In patients with intraabdominal maldescended testis, laparoscopy is useful to see for oneself the pelvic structures, position of the testis and decide upon surgery ( single or staged procedure ).
Surgery becomes more complicated if the blood supply is not ample and elastic enough to be stretched into the scrotum. In these cases, the supply may be divided, some vessels sacrificed with expectation of adequate collateral circulation. In the worst case, the testis must be "auto-transplanted" into the scrotum, with all connecting blood vessels cut and reconnected ("anastomosed").
When the testis is in the abdomen, the first stage of surgery is exploration to locate it, assess its viability, and determine the safest way to maintain or establish the blood supply. Multi-stage surgeries, or autotransplantation and anastomosis, are more often necessary in these situations. Just as often, intra-abdominal exploration discovers that the testis is non-existent ("vanished"), or dysplastic and not salvageable.
The principal major complication of all types of orchiopexy is a loss of the blood supply to the testis, resulting in loss of the testis due to ischemic atrophy or fibrosis.
Upon diagnosis, estrogen and progesterone therapy is typically commenced, promoting the development of female characteristics.
The consequences of streak gonads to a person with Swyer syndrome:
1. Gonads cannot make estrogen, so the breasts will not develop and the uterus will not grow and menstruate until estrogen is administered. This is often given transdermally.
2. Gonads cannot make progesterone, so menstrual periods will not be predictable until progestin is administered, usually as a pill.
3. Gonads cannot produce eggs so conceiving children naturally is not possible. A woman with a uterus and ovaries but without female gamete is able to become pregnant by implantation of another woman's fertilized egg (embryo transfer).
4. Streak gonads with Y chromosome-containing cells have a high likelihood of developing cancer, especially gonadoblastoma. Streak gonads are usually removed within a year or so of diagnosis since the cancer can begin during infancy.
Surgery is sometimes performed to alter the appearance of the genitals. However many surgeries performed on intersex people lack clear evidence of necessity, can be considered as mutilating, and are widely considered to be human rights violations when performed without the informed consent of the recipient.
Most people develop symptoms of estrogen deficiency, including vasomotor flushes and vaginal dryness, both of which respond to hormone replacement therapy. There are several contraindications of estrogen supplement, including smokers over 35 years of age, uncontrolled hypertension, uncontrolled diabetes mellitus, or history of thromboemboli events.
Women younger than 40 year with primary ovarian insufficiency benefit from physiologic replacement of hormones. Most authorities recommend that this hormone replacement continue until age 50 years, the normal age of menopause. The leading hormone replacement regimen recommended involves the administration of estradiol daily by either skin patch or vaginal ring. This approach reduces the risk of pulmonary embolism and deep venous thrombosis by avoiding the first pass effect on the liver that is induced by oral estrogen therapy. To avoid the development of endometrial cancer young women taking estradiol replacement need also to take a progestin in a regular cyclic fashion. The most evidence supports the use of medroxyprogesterone acetate per day for days one through 12 of each calendar month. This will induce regular and predictable menstrual cycles. It is important that women taking this regimen keep a menstrual calendar. If the next expected menses is late it is important to get a pregnancy test. It this is positive, the woman should stop taking the hormone replacement. Approximately 5 to 10% of women with confirmed primary ovarian insufficiency conceive a pregnancy after the diagnosis without medical intervention.
The transdermal estradiol patch is commonly recommended due to several advantages. It provides the replacement by steady infusion rather than by bolus when taking daily pills. It also avoids the first-pass effect in the liver.
Treatment of HH is usually with hormone replacement therapy, consisting of androgen and estrogen administration in males and females, respectively.
The first line of therapy after diagnosis typically involves the administration of the combined oral contraceptive pill, medroxyprogesterone acetate or a gonadotropin-releasing hormone agonist to suppress menstruation and thereby relieve pain. Surgically, cervical agenesis has historically been treated through hysterectomy (removal of the uterus) to relieve symptoms caused by hematocolpos (the accumulation of menstrual fluid in the vagina). Other surgical methods of management involve the creation of an anastomotic connection between the uterus and vagina by neovaginoplasty or recanalization of the cervix. Outcomes in these cases are generally poor, since the natural functions of the cervix—such as mucus production and providing a barrier against ascending infection—cannot be replicated. Furthermore, the success rate of uterovaginal anastomosis is less than 50% and most patients require multiple surgeries while many develop cervical stenotis. Despite this, several pregnancies have been reported in women with cervical agenesis who underwent surgical treatment.
Standard treatment would include surgical exploration via laparotomy. Laparoscopy may be an option if the surgeon is particularly skilled in removing ovarian neoplasms via laparoscopy intact. If the diagnosis of gonadoblastoma is certain, a bilateral salpingo-oophorectomy (BSO) should be performed to remove both the primary tumor and the dysgenic contralateral ovary. If uninvolved, the uterus should be left intact. Modern reproductive endocrinology technology allows patients post BSO to achieve pregnancy via in-vitro fertilization (IVF) with a donor egg.
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.
Treatments vary based on the underlying condition. Key issues are problems of surgical correction if appropriate and oestrogen therapy if oestrogen levels are low. For those who do not plan to have biological children, treatment may be unnecessary if the underlying cause of the amenorrhoea is not threatening to their health. However, in the case of athletic amenorrhoea, deficiencies in estrogen and leptin often simultaneously result in bone loss, potentially leading to osteoporosis.
"Athletic" amenorrhoea which is part of the female athlete triad is treated by eating more and decreasing the amount and intensity of exercise. If the underlying cause is the athlete triad then a multidisciplinary treatment including monitoring from a physician, dietitian, and mental health counselor is recommended, along with support from family, friends, and coaches. Although oral contraceptives can causes menses to return, oral contraceptives should not be the initial treatment as they can mask the underlying problem and allow other effects of the eating disorder, like osteoporosis, continue to develop. Weight recovery, or increased rest does not always catalyze the return of a menses. Recommencement of ovulation suggests a dependency on a whole network of neurotransmitters and hormones, altered in response to the initial triggers of secondary amenorrhoea. To treat drug-induced amenorrhoea, stopping the medication on the advice of a doctor is a usual course of action.
Looking at Hypothalamic amenorrhoea, studies have provided that the administration of a selective serotonin reuptake inhibitor (SSRI) might correct abnormalities of Functional Hypothalamic Amenorrhoea (FHA) related to the condition of stress-related amenorrhoea. This involves the repair of the PI3K signaling pathway, which facilitates the integration of metabolic and neural signals regulating gonadotropin releasing hormone (GnRH)/luteinizing hormone (LH). In other words, it regulates the neuronal activity and expression of neuropeptide systems that promote GnRH release. However, SSRI therapy represents a possible hormonal solution to just one hormonal condition of hypothalamic amenorrhoea. Furthermore, because the condition involves the inter workings of many different neurotransmitters, much research is still to be done on presenting hormonal treatment that would counteract the hormonal affects.
As for physiological treatments to hypothalamic amenorrhoea, injections of metreleptin (r-metHuLeptin) have been tested as treatment to oestrogen deficiency resulting from low gonadotropins and other neuroendocrine defects such as low concentrations of thyroid and IGF-1. R-metHuLeptin has appeared effective in restoring defects in the hypothalamic-pituitary-gonadal axis and improving reproductive, thyroid, and IGF hormones, as well as bone formation, thus curing the amenorrhoea and infertility. However, it has not proved effective in restoring of cortisol and adrenocorticotropin levels, or bone resorption.
This condition will occur if there is an absence of both Müllerian inhibiting factor and testosterone. The absence of testosterone will result in regression of the Wolffian ducts; normal male internal reproductive tracts will not develop. The absence of Müllerian inhibiting factor will allow the Müllerian ducts to differentiate into the oviducts and uterus. In sum, this individual will possess female-like internal and external reproductive characteristics, lacking secondary sex characteristics. The genotype may be either 45,XO, 46,XX or 46,XY.
Treatment includes androgen (testosterone) supplementation to artificially initiate puberty, testicular prosthetic implantation, and psychological support. Gender Dysphoria may result in anorchic individuals who are assigned male at birth and raised as male despite lacking the necessary masculinizing hormones during prenatal, childhood, and adolescent development. Anorchic individuals who have a female identity may be administered estrogen alone in place of testosterone as no androgen blockers are necessary due to the lack of gonads.
During embryogenesis, without any external influences for or against, the human reproductive system is intrinsically conditioned to give rise to a female reproductive organisation.
As a result, if a gonad cannot express its sexual identity via its hormones—as in gonadal dysgenesis—then the affected person, no matter whether their chromosomes are XY or XX, will develop external female genitalia. Internal female genitalia, primarily the uterus, may or may not be present depending on the cause of the disorder.
In both sexes, the commencement and progression of puberty require functional gonads that will work in harmony with the hypothalamic and pituitary glands to produce adequate hormones.
For this reason, in gonadal dysgenesis the accompanying hormonal failure also prevents the development of secondary sex characteristics in either sex, resulting in a sexually infantile female appearance and infertility.
The consequences to the girl with XX gonadal dysgenesis:
1. Her gonads cannot make estrogen, so her breasts will not develop and her uterus will not grow and menstruate until she is given estrogen. This is often given through the skin now.
2. Her gonads cannot make progesterone, so her menstrual periods will not be predictable until she is given a progestin, still usually as a pill.
3. Her gonads cannot produce eggs so she will not be able to conceive children naturally. A woman with a uterus but no ovaries may be able to become pregnant by implantation of another woman's fertilized egg (embryo transfer).
Treatment may consist of surgery in the case of tumors, lower doses of estrogen in the case of exogenously-mediated estrogen excess, and estrogen-suppressing medications like gonadotropin-releasing hormone analogues and progestogens. In addition, androgens may be supplemented in the case of males.
Swyer syndrome, or XY gonadal dysgenesis, is a type of hypogonadism in a person whose karyotype is 46,XY. The person is externally female with streak gonads, and if left untreated, will not experience puberty. Such gonads are typically surgically removed (as they have a significant risk of developing tumors) and a typical medical treatment would include hormone replacement therapy.
The syndrome was named by Gerald Swyer, an endocrinologist, based in London, United Kingdom.
Anorchia (or anorchism) is an XY disorder of sex development in which individuals have both testes absent at birth. Within a few weeks of fertilization, the embryo develops rudimentary gonads (testes), which produce hormones responsible for the development of the reproductive system. If the testes fail to develop within eight weeks, the baby will develop female genitalia (see Swyer syndrome). If the testes begin to develop but are lost or cease to function between eight and 10 weeks, the baby will have ambiguous genitalia when it is born. However, if the testes are lost after 14 weeks, the baby will have partial male genitalia with the notable absence of gonads.
Tests include observable lack of testes, low testosterone levels (typical female levels), elevated follicle stimulating hormone and luteinizing hormone levels, XY karyotype, ultrasound or magnetic resonance imaging showing absent gonadal tissue, low bone density, low anti-Müllerian hormone levels, and surgical exploration for evidence of male gonadal tissue.
Exposure of a male fetus to substances that disrupt hormone systems, particularly chemicals that inhibit the action of androgens (male sex hormones) during the development of the reproductive system, has been shown to cause many of the characteristic TDS disorders. These include environmental estrogens and anti-androgens found in food and water sources that have been contaminated with synthetic hormones and pesticides used in agriculture. In historical cases, medicines given to pregnant women, like diethylstilbestrol (DES), have caused many of the features of TDS in fetuses exposed to this chemical during gestation. The impact of environmental chemicals is well documented in animal models. If a substance affects Sertoli and Leydig cell differentiation (a common feature of TDS disorders) at an early developmental stage, germ cell growth and testosterone production will be impaired. These processes are essential for testes descent and genitalia development, meaning that genital abnormalities like cryptorchidism or hypospadias may be present from birth, and fertility problems and TGCC become apparent during adult life. Severity or number of disorders may therefore be dependent on the timing of the environmental exposure. Environmental factors can act directly, or via epigenetic mechanisms, and it is likely that a genetic susceptibility augmented by environmental factors is the primary cause of TDS.
Links between maternal smoking and TDS are tenuous, but there are stronger associations between maternal alcohol consumption and incidences of cryptorchidism in sons. Smoking does however affect the growth of a fetus, and low birth weight is shown to increase the likelihood of all the disorders encompassed by TDS. Maternal obesity, resulting in gestational diabetes, has also been shown to be a risk factor for impaired testes development and TDS symptoms in sons.
Pseudohermaphroditism, or pseudo-hermaphroditism, is an old clinical term for an organism is born with primary sex characteristics of one sex but develops the secondary sex characteristics that are different from what would be expected on the basis of the gonadal tissue (ovary or testis). It can be contrasted with the term true hermaphroditism, which described a condition where testicular and ovarian tissue were present in the same individual. This language has fallen out of favor due to misconceptions and pejorative connotations associated with the terms, and also a shift to nomenclature based on genetics.
The term "male pseudohermaphrodite" was used when a testis is present, and the term "female pseudohermaphrodite" was used when an ovary is present.
In some cases, external sex organs associated with pseudohermaphroditism look intermediate between a typical clitoris and penis. In other cases, the external sex organs have an appearance that would be expected to be seen with the "opposite" gonadal tissue. Because of this, pseudohermaphroditism is sometimes not identified until puberty or adulthood.
Associated conditions include 5-α-reductase deficiency and androgen insensitivity syndrome.