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Hermaphroditism

When the gonads in one individual are comprised of both ovarian and testicular elements, the condition is called true hermaphroditism. The most common gonad found is an ovotestis, and gonads with purely ovarian tissue are more likely to be found on the left side true hermaphroditism, hermaphrodite, hermafrodite, hermaprodite. In most cases, any testicular tissue found is dysgenetic, and the ovarian tissue is normal true hermaphroditism, hermaphrodite, hermafrodite, hermaprodite. Most patients with true hermaphroditism have ambiguous genitalia. Between 50% and 97% of patients with true hermaphroditism are 46,XX or mosaic. In addition, true hermaphroditism may be familial. On the basis of extensive studies carried out in the much-affected Bantu-speaking people of southern Africa, the risk for gonadal malignancy seems to be much lower (about 2%) than in either the complete or partial forms of XY gonadal dysgenesis. Although most patients with true hermaphroditism are infertile, in one series, 21 pregnancies were reported in 10 women with true hermaphroditism, and one male with the

The exact nature of true hermaphroditism is puzzling. In general, germline SRY mutations have not been found in 46,XX subjects, but there are exceptions. In SRY mutation-negative cases, the most likely explanation for true hermaphroditism is inappropriate activation of testicular differentiation at a

One group has reported finding a postzygotic somatic mutation in the SRY gene in the gonad but not the blood. Studies of XY gonadal hermaphroditism in an experimental animal model show that both true hermaphroditism and partial gonadal dysgenesis can stem from a common etiology and seem more like different parts of the same spectrum than distinct and

In humans, there are several distinct differences between true hermaphroditism and gonadal dysgenesis. Patients with true hermaphroditism are usually XX, whereas in gonadal dysgenesis, a Y chromosome is usually present. The risk of malignancy is low in true hermaphroditism but high in gonadal dysgenesis. True hermaphroditism occurs as a familial disorder, whereas gonadal dysgenesis is less commonly familial. Rarely, true hermaphroditism is believed to occur as the result of the simultaneous fertilization of two eggs that then fuse. In a unique case, true hermaphroditism occurred following in vitro fertilization with the implantation of multiple embryos. In this case, the postulated mechanism was the fusion of two embryos, one XX and

If the patient has an XX karyotype and ambiguous genitalia, the most likely diagnosis is congenital adrenal hyperplasia owing to 21-hydroxylase deficiency. This condition results in increased ACTH secretion, which, in turn, results in hyperpigmentation of the genital skin. An infant with both ambiguous genitalia and hyperpigmented genital skin has impaired adrenocortical function until

On the basis of data collected during neonatal screening, the incidence of 21-hydroxylase deficiency is 1 in 14,500. Only affected females have ambiguous genitalia, which is caused by the ACTH-stimulated hypersecretion of adrenal androgens. Development of the ovaries and internal female reproductive organs is unaffected. Because enzyme activity is reduced to practically zero in the salt-wasting form and to approximately 1% in the simple virilizing form, the conversion of 17alpha-hydroxyprogesterone to

The combination of ambiguous genitalia and hyperpigmented genital skin is seen with several other steroidogenic defects including 11beta-hydroxylase deficiency, lipoid adrenal hyperplasia, and 3beta-hydroxysteroid dehydrogenase deficiency. These are all