Human Reproduction Vol.21, No.12 pp. 3303–3304, 2006 © The Author 2006. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. 3303 For Permissions, please email: journals.permissions@oxfordjournals.org Letter to the Editor Evolution, morality and the law: on Valerie J. Grant's case against sex selection Sir, In her intriguing paper 'Sex predetermination and the ethics of sex selection', psychologist Valerie J. Grant argues that the sex of our offspring may not be a matter of chance. Growing evidence from behavioural ecology and evolutionary psychology seems to suggest that women give birth to children they are best suited to raise. Women who are better suited to raise boys bear sons and women who are better suited to raise girls bear daughters (Grant, 2006). Being a moral philosopher, I am in no position to dispute Grant's empirical claim. I am, however, very much in the position to dispute her normative claim. Her theory does not have the policy implications she thinks it has. If she were right, we would certainly have to inform couples seeking sex selection about her theory. Perhaps, we would have to go even one step further and try to dissuade mothers of three sons from having a daughter. However, we cannot prevent parents from choosing the sex of their children, leave alone, outlaw social sex selection altogether (Dahl, 2003). In claiming that we need to know more about the alleged behavioural differences between mothers of sons and mothers of daughters 'before allowing people who are particularly suited to raising one sex to try their hand at the other', she ignores the presumption in favour of liberty underlying Western policy-making. According to the presumption in favour of liberty, each citizen has the right to live his life as he sees fit, provided that in doing so he is not violating the rights of others. The legislator may interfere with the free choices of its citizens only to prevent serious harm to others (Dahl, 2004). The presumption in favour of liberty implies that the burden of proof is always on those who wish to prohibit a particular action. It is they who must show that the action in question is going to harm others. In the absence of any evidence of serious harm to others, there is simply no moral justification to prevent couples from choosing the sex of their children. In other words, social sex selection is innocent until proven guilty (Dahl, 2005). Let us assume, if only for argument's sake, that Grant were able to provide us with conclusive evidence that children born after social sex selection are indeed seriously harmed. Suppose, it could be shown that, say, girls raised by a mother particularly suited to raise boys were at risk of being abused, neglected or abandoned. Would this be the end of social sex selection? Not at all! Why not? Because Grant's hypothesis actually calls for a new indication for social sex selection. According to Grant, in natural reproduction, women conceive and give birth to children they are best suited to raise. In assisted reproduction, however, there is a substantial risk that artificial insemination, IVF and, most of all, ICSI may circumvent the 'finely tuned adaptation' that allows a woman to bear the children she is best suited to raise. If so, fertility centres would be morally obliged to screen spermatozoa and embryos for their chromosomal sex before assisting a woman in conceiving a child. In other words, fertility specialists should not leave the sex up to chance any longer but practise social sex selection. After all, sex selection would be the optimal way to ensure that women undergoing fertility treatment are really going to have the children they are best suited to raise. References Dahl E (2003) Procreative liberty: the case for preconception sex selection. Reprod Biomed Online 7,380–384. Dahl E (2004) The presumption in favour of liberty: a comment on the HFEA's public consultation on sex selection. Reprod Biomed Online 8, 266–267. Dahl E (2005) Sex selection: laissez faire or family balancing? Health Care Anal 13,87–90. Grant VJ (2006) Sex predetermination and the ethics of sex selection. Hum Reprod 21,1659–1661. E.Dahl Spokesman of the German Society for Reproductive Medicine, Centre for Gynaecology and Obstetrics, Medical Centre of the University of Giessen and Marburg Ltd., Giessen, Germany E-mail: presse@repromedizin.de doi:10.1093/humrep/del347 Advance Access publication October 23, 2006 Reply: Evolution, morality and the law: on Valerie J. Grant's case against sex selection Sir, In offering my article for publication (Grant, 2006), I was making a tentative suggestion to defer the decision on whether or not sex selection for social reasons should be permitted, until we know more about the processes of sex determination, or, as I argued, sex predetermination. But in his response to this idea, Dahl (in press) has leapt well into the future, to a place I had not yet imagined! And yes, I see the logic of his position. If, as I suggest, there is such a thing as sex predetermination in mammals, and if an adaptive, and possibly important, process underlies it, I should withdraw my objection to sex selection and instead argue in favour of it. If my hypotheses were shown to be correct, it might indeed mean that fertility specialists would practise sex selection, Letter to the Editor 3304 simply to increase the chances of success. But the word 'social' would be the wrong one to describe this new preselection process; rather, this new process would need to be based on the physiological and psychological attributes of the mother-to-be. Consider, then, the case of a mother seeking to select the sex of her next child with a view to family balancing. If she had not changed along the relevant dimensions since her last pregnancy, she would be very unlikely to conceive a child at all. And if she did, it would probably mean that she would have conceived a child of the desired sex without any technical intervention. Even though these hypothesized new processes for sex preselection could result in reducing the choices for parents of single-sex sibships, interventions that took into account the physiological and psychological attributes of the mother might increase conception rates in previously infertile women. At the present time, it could be that the low fertility rates following some common procedures (especially intracytoplasmic sperm injection) do not reflect a lack of technical expertise, but rather the possibility that the mother has some role in the predetermination and/or the ratification of the sex of her infant. But all this is speculative and even if supported by research, it is some way into the future, especially for human sex selection. In the meantime, I have found no research evidence that adoptions carried out for the purpose of family balancing are seriously harmful. Dahl (in press) assumes, wrongly, that I was suggesting that children adopted under such conditions might be 'at risk of being abused, neglected or abandoned'. But this is too extreme to describe what is more likely to be a mismatch between parental style and child characteristics. Such a mismatch simply means that the parents and the child, particularly the mother and the child, never really get on together or that the family style never really suits the adopted child (or the child whose sex has been preselected) in the way it has suited the natural children of the opposite sex. This lesser disadvantage means that one could not argue that there would be sufficient harm to warrant a legal restriction on procreative liberty. It could, however, mean that the case for the parental virtue of acceptance is enhanced (McDougall, 2005). References Dahl E (in press) Evolution, morality and the law: on Valerie J. Grant's case against sex selection. Hum Reprod. Grant VJ (2006) Sex predetermination and the ethics of sex selection. Hum Reprod 21,1659–1661. McDougall R (2005) Acting parentally: an argument against sex selection. J Med Ethics 31,601–605. V.J.Grant PhD, Department of Psychological Medicine, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand E-mail: vj.grant@auckland.ac.nz doi:10.1093/humrep/del348 Advance Access publication October 23,