Debate over gender disorder drug

What is the treatment, and what is it used for at present?

The treatment is for a condition called congenital adrenal hyperplasia (CAH), which affects about 1 in 15,000 babies. Fetuses affected by CAH have gene defects which mean that they either can't make or don't make enough of a key adrenal hormone called 21-hydroxylase.

That means that their adrenal glands carry on producing male hormones long after they should have stopped. Boys' sexual organs are not affected by this, but about 1 in 8 female fetuses with the condition develop genitalia with masculine characteristics, such as a large clitoris. Girls may also have their urethra positioned inside the vagina, for example.

At birth doctors and parents may have difficulty deciding the gender of girls affected this way, and many go on to have surgery to correct the physical abnormalities. But a group of researchers led by Maria New of the Mount Sinai Medical Center in New York have been testing a treatment that prevents the anatomical abnormalities in the womb. It means giving a pregnant woman at risk of having a child with CAH a drug called dexamethasone (dex) starting as early as five weeks after conception. The drug keeps male hormones at a normal level, reducing the possibility of the anatomical defects, though it has no effect on their CAH – people with the disorder will continue to take medication throughout their life.

How might such a treatment stop girls being gay?

The majority of girls with CAH are heterosexual. One of the hallmarks of girls who have CAH is that they are more likely to be tomboyish, to avoid having children in adulthood, and are slightly more likely than the average girl to be gay or bisexual.

New and colleagues have already treated about 600 pregnant women with dexamethasone to try and prevent their baby girls from developing the anatomical problems. More recently the team has begun to document how the girls develop cognitively – to make sure their intelligence is not damaged by the treatment – and how they develop behaviourally and sexually.

One theme that is beginning to emerge from their presentations at conferences and their published work is the potential for dexamethasone treatment to make the behaviour and sexuality of the girls less masculine. Theoretically, this could mean that by giving CAH girls dexamethasone, they avoid developing the "masculinised" brain architecture that might otherwise increase the girls' likelihood of becoming bisexual or gay.

Have any fetuses been treated with the sole intention of making them straight?

No. And at present, no one is even proposing doing this.

So what's all the fuss about then?

The worry is that a treatment used to prevent the anatomical masculinisation of girls' genitalia in the womb might in future be commandeered to prevent homosexuality in girls with CAH.

Who has highlighted these concerns?

A group of bioethicists and paediatricians, led by Alice Dreger of the Northwestern University Feinberg School of Medicine in Chicago. Dreger and others have voiced their concerns in the Bioethics Forum of the Hastings Center in New York.

Have New or her colleagues said that they want to use dex to influence the sexuality of girls with CAH?

No. New and her Mount Sinai colleague, Saroj Nimkarn, wrote earlier this year in the Annals of the New York Academy of Sciences, (DOI: 10.1111/j.1749-6632.2009.05225.x) that "we anticipate that prenatal dexamethasone therapy will reduce the well-documented behavioural masculinisation and difficulties related to reconstructive surgeries".

Heino Meyer-Bahlburg, a clinical psychologist at Columbia University in New York and long-time collaborator with New has emphasised that he had no intention of ever recommending dexamethasone to "treat" homosexuality.

Is there a possibility that dex could have side effects?

Meyer-Bahlburg said that his studies of the impact of dexamethasone on behaviour and cognition were prompted by studies of dex in fetal animals showing that at usually much higher doses than in the human treatments, they suffered a range of abnormalities, including low birth weight, cleft palate, liver enlargement, and central nervous system effects. Now, he's monitoring girls who had dexamethasone in the womb to see how they develop behaviourally and sexually.

Where does that leave the treatment?

It seems that using it to prevent homosexuality is simply off the radar. "I am not aware of any treatment offered solely on the basis of influencing gender development, or even mentioned as an "added value" to the raison d'etre of treating to prevent virilisation," says Ieuan Hughes of Addenbrooke's Hospital in Cambridge.

Most researchers agree that the use of dex to correct anatomical defects is justified, and preferable to surgery after birth. "It would be wrong to simply say stop," says David Sandberg of the University of Michigan in Ann Arbor.

In the next month, the US Endocrine Society will be publishing new guidelines for CAH treatment which clarify that dexamethasone should be given to fetuses with CAH only in the context of fully approved clinical trials.