To understand how some individuals can have indeterminate genitalia we need to understand how the external genitals develop. The basic human body pattern is female, but if testes are present this changes in the womb. The external labia fuse together to become the scrotum and the clitoris enlarges to become this penis. The line of this junction is called the raphe, and is visible from the base of the scrotum to the frenulum. Since this process is driven by hormones, hormonal problems can interfere with it.
Intersex bodies can also result from chromosome abnormalities. A normal male has one X chromosome ond one Y chromosome (abbreviated to XY) and a normal female is XX. In general if a Y chromosome is present the resulting phenotype will be predominantly male. Relatively common variants are XXY, Klinefelter's syndrome, and XO, Turner's syndrome. Both produce apparently normal bodies in infancy, but they will not go through normal puberty (unless given hormona treatment) and will not be fertile. They are not an issue when it comes to circumcision - circumcising a Klinefelter's boy will do no harm, and will confer all the health benefits it gives to a normal boy.
It is the hormonal issues which normally concern us. One of the commmonest of these is over-activity of the adrenal glands in the foetus (chronic adrenal hyperplasia, or CAH). This leads to masculinization of the external genitals in a baby which, internally, is female. The extent can be very variable, from an enlarged clitoris in an otherwise female body, to genitals which look completely masculine (left). The female internal organs are, in most cases, normal so that the adult can be fertile. Another effect of this condition is abnormal salt metabolism.
This boy should not have been circumcised. Why? Because he is not a boy. At birth he appeared to be a normal boy, withe undescended testes (not uncommmon, see below). As usual, in the US, he was circumcised. At 3 months he was admitted to hospital with a salt metabolism crisis, at which point it was realised that 'he' was an XX female with CAH and totally masculinised genitals. At this juncture the important thing is to do nothing. As with any other child with ambiguous genitals, it is vital to wait until it is clear what sex the child identifies with before considering any surgical intervention.
From RS Hurwitx & AA Caldamone, 2012. Anatomic contraindications to circumcision. Chapter 5 in Surgical Guide to Circumcision, ed Bolnick, Koyle & Yosha, Springer.
It is really important that this condition is recognised early - undescended testes (see below) are not an important issue at this age, and certainly are not a reason for not circumcising, but they should trigger an investigation to see if there is a more important underlying problem.
5-alpha reductase deficiency
This enzyme deficiency interferes with the production of dihydrotestosterone, so that foetal masculinization is inhibted even though the boy is genetically male. The external genitals appear female at birth, but penis and testes are present and emerge at puberty. The Pulitzer Prize novel Middlesex by by Jeffrey Eugenides deals with this condition. Rearing such a child as a girl can be a source of major trauma,
All such birth defects should be regarded as contra-indications to neonatal circumcision. Genital surgery of any nature (not just circumcision) must be deferred until a complete, specialist assessment of the intersex condition has been carried out.
Particularly in cases where there is a marked discrepancy between physical genitalia and chromosomal gender, psychometric investigation as well as genetic and physical examinations will be required. As far as possible the genitalia should be left as they are found at least until such time as the child has settled into their freely chosen gender role. Only once the individual is able to express an informed, experiential opinion regarding their sexuality should any gender assignment surgery be contemplated.
A word here about bilateral cryptorchidism, which is something of a special case. It can be an indicator of an intersex condition, but it is not necessarily an indicator of an intersex condition. If the parents so choose, such a boy can be circumcised as soon as the absence of any abnormality other than cryptorchidism has been established. There is no absolute need to wait until the orchidopexy surgery is performed, although that is an option.
The incidence of intersex conditions is reported by the Intersex Society of North America (ISNA) as being approximately 1 in 2000 live births. Readers with personal experience of this subject are advised to contact either ISNA, the United Kingdom Intersex Association or their own national support group.
Androgen Insensitivity Syndrome (AIS) Support Group Australia Inc.
Intersex Awareness New Zealand
Intersex.ch (German language/Swiss dialect)
Intersex Society of North America
United Kingdom Intersex Association
The Online Learning facilities of Chulalongkorn University Faculty of Medicine, Bangkok. Ellaithi, M., et al., BMC Pediatrics 2006 6:11 reporting fieldwork conducted in the Sudan. Nistal, M., et al., Usefulness of gonadal biopsy in the diagnosis of sexual developmental disorders. Actas Urol España. 2007; 31(9):1056-1075. The website of the United Kingdom Intersex Association. The website of the University of California (UCAL), Santa Barbara.