February 26, 2024

Marriage of unwitting twins sparks IVF debate

Brother and sister separated at birth and adopted out marry after “irresistible attraction”

The marriage of British twins separated at birth has startled the UK and raised fears of unwitting incest due to anonymous egg and sperm donors. The case was disclosed by Lord Alton during a debate in the House of Lords on new fertility legislation. Their marriage was quietly annulled last year, with a judge ruling that it had never existed. They had met as adults and felt “an irresistible attraction”. Lord Alton used the case to argue that that birth certificates should be changed to include information on both genetic parents, as well as whether or not the child was conceived by a sperm donor. He described anything less as a violation of human rights: “The state is colluding in a deception. We are opening the door to more cases like this one.”

The tragic case highlighted the growing possibility of unwitting incest in the population, now that as many as one child in 25 is born through IVF in some countries. Back in 2002, an Australian researcher called for free DNA testing to avoid the dangers of inbreeding. Dr Panos Ioannou wrote in the journal Nature that “In most cultures, at least a small percentage of children are born through infidelity. Added to that, as many as 10% of couples now use assisted reproduction, often involving the use of gametes from unknown donors. Children born through such practices are likely to be of similar ages and to grow up in the same area. A significant percentage of couples may, unknowingly, be closely related.”

The problem could be particularly acute in the US where there is  almost no regulation of IVF, even though the technology is responsible for about 1% of all births. “As half-siblings find one another, it is becoming clear that the banks do not know how many children are born to each donor, and where they are. Popular donors may have several dozen children and critics say there is a risk of unwitting incest between half-siblings,” the New York Times has reported.

And the soap opera scenario of “irresistible attraction” may have a scientific basis, although there is only anecdotal evidence for it at the moment. Post-adoption agencies say that nearly half of reunions between siblings or parents and offspring result in obsessive attachments and emotions which sometimes lead to incest. “Genetic sexual attraction associated with IVF births is a time bomb waiting to go off,” Sue Cowling, the deputy director of the Post-Adoption Centre in the UK, warned a few years ago. ~ Guardian, May 17, 2003; New York Times, Nov 20, 2005; Nature, Sept 19, 2002; London Times, Jan 13

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3 thoughts on “Marriage of unwitting twins sparks IVF debate

  1. Not many people seem to have noticed the follow-up to this story in The Guardian 15 January 2008. See

    This presents pretty compelling arguments for treating it as an urban myth that conveniently suited the particular normative agenda being pursued by one of the UK’s most prominent Roman Catholic laymen….

  2. INADVERTENT CONSANGUINITY is more probable for infidelity.
    Infidelity current research consistently shows that 10% of all children are the product of infidelity. Only 1 % of the world population require gamete donation fertility procedures and only half of them will get a pregnancy.
    The American Society for Reproductive Medicine, have advised an arbitrary limit of no more than 25 pregnancies per sperm or oocyte donor, in a population of 800,000, in order to minimize risks of consanguinity (2?4). This suggestion may require modification if the population using donor gametes represents an isolated subgroup or the specimens are distributed over a wide geographic area.

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