General Medical Information

True Hermaphroditism

Joe Leigh Simpson

True hermaphrodites have both ovarian and testicular tissue. They may have a separate ovary and a separate testis or, more often, one or more ovotestes. Most true hermaphrodites (60%) have a 46,XX chromosomal complement; however, a minority have 46,XX/46,XY, 46/XY, 46,XX/47,XXY, or other complements. Phenotype probably reflects karyotype, but it is preferable here only to generalize about the phenotype of all true hermaphrodites.

If there is no medical intervention (obviously now a rarity in most venues), two thirds of true hermaphrodites would be raised as males. By contrast, external genitalia usually are ambiguous or predominantly female. Breast development usually occurs at puberty, even with predominantly male external genitalia. Gonadal tissue may be located in the ovarian, inguinal, or labioscrotal regions. A testis or an ovotestis is more likely to be present on the right than on the left. Spermatozoa are rarely present; however, apparently normal oocytes often are present, even in ovotestes 46,XX true hermaphrodites have even become pregnant, usually but not always after removal of testicular tissue.

The greater the proportion of testicular tissue in an ovotestis, the greater the likelihood of gonadal descent. In 80% of ovotestes, testicular and ovarian components are juxtaposed end to end. Thus, an ovotestis may be detectable by inspection or palpation, because testicular tissue is softer and darker than ovarian tissue. Accurate identification by ultrasound or magnetic resonance imaging is particularly necessary if the inappropriate portion of the ovotestis is to be extirpated. Both gonadal neoplasia and breast carcinoma have been reported. The former may reflect risks associated with the intraabdominal location of testicular tissue.

A uterus usually is present, although sometimes it is bicornuate or unicornuate. Absence of a uterine horn usually indicates ipsilateral testis or ovotestis. The fimbriated end of the fallopian tube may be occluded ipsilateral to an ovotestis, and squamous metaplasia of the endocervix may occur. Menstruation is not uncommon and may be manifested as cyclic hematuria.

Presence of a uterus is diagnostically useful in true hermaphroditism and is particularly invaluable in the rare 46,XY cases. Of individuals with genital ambiguity having a chromosome, only 46,XY hermaphrodites and 45,X/46,XY mosaics have a uterus.

Diagnosis usually is made only after excluding male and female pseudohermaphroditism. If a female sex of rearing is chosen, extensive surgery may or may not be necessary. If a male sex of rearing is chosen, genital reconstruction and selective gonadal extirpation are invariably indicated.