Rarely, however, do parents wish their new addition to be “the right sex”. Maternity wards do not echo with the grumbles of disappointed couples, encumbered for the next 18 years with an infant of the “wrong” sex. If we met people brave or silly enough to voice such misgivings, would we not wonder whether they were fit to be parents at all?

There is something intrinsically wrong with choosing one sex over another. By implication choosing one suggests that the other is somehow inferior. “Sex selection” is also a step closer to turning children into commodities. That is why the Human Fertilisation and Embryology Authority (HFEA) is right to maintain the status quo on sex selection. Unfortunately, it was not brave enough to claim the moral high ground, instead pinning its decision on public opinion. It has ruled that parents may choose the sex of their children if there are sound medical grounds for doing so — for example, to prevent the inheritance of a serious sex-linked disorder such as Duchenne’s muscular dystrophy — but that parents cannot elect to have a boy or a girl for social reasons.

The decision is a blow for the libertarian brigade, who believe that parental choice should begin in the womb. Bob Edwards, the IVF pioneer, once told me: “Go ahead and use it (sex selection). Those parents have to raise those children. Why should a politician tell me what I can and can’t do?” But the libertarians will probably get their way: controversial, frontier technology eventually becomes mainstream. It has taken only one generation for in-vitro fertilisation, once denounced as the work of the devil, to become available on the NHS.

For now, though, the HFEA says that the technology is not foolproof and that children born who are not of the desired sex may suffer psychological harm. However, the main thrust of the authority’s decision is based on a public consultation exercise showing that 80 per cent of the public opposed sex selection for social reasons. It also cites a MORI poll in support, concluding that public opposition is “clear and consistent”.

The authority acknowledges the slippery slope argument — that the use of technology to select for one non-medical characteristic, in this case sex, opens the door to the selection of others. Before you know it, a prospective baby is not so much a glint in its father’s eye as a page in a Babies ‘R’ Us catalogue.

But by making public opinion the centrepiece of its decision-making, especially on an emotive issue such as assisted reproduction, the HFEA is on a slippery slope of its own. After all, there was great public sympathy for Alan and Louise Masterton, who have four sons but had lost their only daughter, Nicole, in an accident. They sought permission from the HFEA to choose a female embryo for “family balancing” reasons. The HFEA said no.

The public likewise supported Dianne Blood’s use of her dead husband’s sperm to conceive. Concerned that Mr Blood had not given his explicit, written consent, the HFEA refused permission for Mrs Blood to be inseminated. Mrs Blood appealed and won. The HFEA was condemned for its heartlessness. The formidable Ruth Deech, who was then chairman of the HFEA, later asked me to think of the public disquiet that would have ensued if a man had requested that his dead wife be kept alive so that her eggs could be harvested.

She had a powerful point. Even though she was overruled, Deech correctly chose the difficult path over the popular one. Sometimes, Deech explained, you have to be arrogant enough to say the public is wrong and you know better. Her approach would give us a better ethical policy than relying on that fickle creature, the public. I hope the HFEA would have been arrogant enough to say it knows better, and that every baby is a gift to be cherished unconditionally, regardless of its sex

The author writes on science and health issues for The Times

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