U.S. physicians have reportedly started a clinical trial to assess the effects of allowing couples to choose the gender of unborn children.
The journal Nature said doctors can use a technology called preimplantation genetic diagnosis to examine the sex of embryos that they create by assisted reproduction. Couples then select male or female embryos to implant in the mother's uterus.
But doing this for non-medical reasons is banned in many nations -- including Britain and Canada -- for fear it would cause sex discrimination.
The research under way in Houston began last month and will look at the babies' health as well as social factors in the families as the children age.
The researchers told Nature they have a waiting list of at least 50 couples, but they will only enroll those who already have a child and who wish to have a child of the opposite sex -- an approach referred to as "family balancing."
Copyright 2005 by United Press International
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