Bioethics & medical ethics
Should People Be Able to Choose the Sex of Their Children?
LNAT Section B · Model essay
The essay prompt
As reproductive technology advances, should parents be permitted to select whether their child is born male or female? If choice is allowed at all, where should the line fall?
The stance
No. Outside the narrow case of avoiding a serious sex-linked disease, people should not be permitted to choose their child's sex. Reproductive liberty is real but bounded, and non-medical sex selection trades a private preference against equality, the dignity of the child and the integrity of medicine. The settled UK, Canadian and Council-of-Europe positions get this right.
Defining the terms
- "Choosing the sex" means deliberate, non-accidental selection of a child's biological sex before birth, through sperm sorting, IVF with pre-implantation screening, or selective abortion. It is not the same as merely learning a child's sex during pregnancy.
- "Should be able to" asks both whether the law ought to permit it and whether it is morally defensible, which are linked but not identical: a thing can be lawful yet wrong, or restricted yet harmless.
- "Non-medical" sex selection means choice driven by preference, family balancing or cultural pressure, as opposed to "medical" selection to avoid a serious sex-linked genetic disorder such as haemophilia or Duchenne muscular dystrophy.
- "Reproductive liberty" is the freedom to make decisions about whether and how to have children; the essay accepts it as weighty but denies that it is unlimited.
Assumptions to interrogate
- That parental autonomy over reproduction extends not just to whether to have a child but to designing a fixed characteristic of that child.
- That sex is a morally neutral preference rather than a trait saturated with cultural and social bias.
- That individual private choices, aggregated across a population, leave collective equality untouched.
- That a legal line drawn at sex selection can be held, and will not slide toward wider trait selection.
The case for
Reproductive autonomy: intimate family decisions belong to parents, not the state.
Liberal societies leave childbearing decisions to individuals because they are deeply personal and self-regarding. On a Millian view, where a choice harms no identifiable third party the state should not interfere. Family balancing, for a couple who already have three sons and want a daughter, looks like exactly the kind of private decision the law should leave alone.
It is already a continuum: we accept many parental choices.
Parents lawfully use IVF, prenatal screening, donor selection and even abortion. They choose schools, diets and upbringing. Retentionists of choice argue that adding sex to that list is a difference of degree, not kind, and that singling sex selection out for prohibition is inconsistent line-drawing dressed up as principle.
In a balanced, regulated society the demographic risk is low.
The catastrophic sex-ratio distortions seen in some countries reflect intense son preference and weak rights for women, not sex selection as such. In a pluralistic society where many couples would choose girls and many boys, and where regulators could cap or monitor, the aggregate population effect might be negligible, removing the strongest practical objection.
The case against
Demographic harm: private preferences aggregate into population-level injustice.
Where son preference exists, free sex selection produces skewed sex ratios. The natural ratio is about 105 boys per 100 girls; China and parts of India have run well above 110, and the UNFPA estimates roughly 142 million "missing" women and girls worldwide. On Mill's own harm principle, autonomy stops where it inflicts this scale of collective harm, and regulators cannot reliably police millions of private motives.
Commodification: the child becomes a product specified by the parent.
Selecting a child's sex shifts procreation from acceptance toward manufacture. Michael Sandel's argument in The Case Against Perfection is that designing children expresses a "drive to mastery" that erodes the "openness to the unbidden" at the heart of parental love. To choose the sex is to treat the child, in Kantian terms, partly as a means to the parents' preference rather than as an end.
It entrenches gender stereotyping and discrimination.
To prefer a particular sex is to act on beliefs about what that sex will be like, reviving the idea that gender is destiny. CEDAW's Joint General Recommendation No. 31 (2014) names prenatal sex selection as a harmful practice rooted in son preference and the disempowerment of women, precisely because choosing a sex affirms that sex is something worth ranking and selecting.
Slippery slope to wider genetic design.
Sex selection normalises the logic of choosing a child's traits. The Oviedo Convention (Article 13) and UNESCO's 1997 Universal Declaration on the Human Genome bar heritable genetic modification for non-therapeutic ends, and the 2018 He Jiankui CRISPR case, which led to a three-year prison sentence in China, shows how fast "innovation" crosses into eugenic territory once the line moves from healing to tailoring.
The argument, step by step
- Distinguish medical from non-medical selection and concede the narrow medical case at the outset, so the argument targets only preference-driven choice.
- Ground the stance: reproductive liberty is weighty but bounded by harm, dignity and equality, so the question is not whether parents have rights but where those rights end.
- Demographic argument first, because it is the hardest-edged: aggregated private preferences distort sex ratios, and Mill's harm principle licenses limiting autonomy that produces this collective harm.
- Move from the empirical to the philosophical: even a perfectly balanced society faces the commodification objection, that designing a child's sex treats the child as a specified product.
- Add the equality dimension: sex preference is never neutral; it operationalises gender stereotype, which is why CEDAW treats it as a harmful practice.
- Close the trajectory argument: sex selection is the first step that normalises trait design, against which Oviedo, UNESCO and the He Jiankui case mark the boundary.
- Comparative confirmation: the UK (HFE Act 2008), Canada (AHR Act 2004) and the Council of Europe (Oviedo) have all drawn the line at non-medical selection, suggesting the prohibition is a considered cross-jurisdictional judgement, not a parochial squeamishness.
- Conclude: permit medical selection to prevent serious sex-linked disease, prohibit the rest.
The model plan
Stance up front: no non-medical sex selection; concede the medical exception. Intro (~90 words): distinguish medical from non-medical choice, accept reproductive liberty but call it bounded, signpost four objections plus comparative law. Para 1 - demographic harm: natural ratio ~105:100, China/India above 110, UNFPA ~142m missing women; Mill's harm principle limits autonomy that aggregates into population injustice; regulators cannot police private motives at scale. Para 2 - commodification: Sandel's "drive to mastery" and the move from acceptance to manufacture; Kantian means/ends; concede parents already make choices, rebut that pre-birth identity selection differs in kind from post-birth nurture. Para 3 - stereotyping and equality: choosing a sex acts on beliefs about that sex; CEDAW GR No. 31 names prenatal sex selection a harmful practice; balanced "family balancing" still instrumentalises gender. Para 4 - slippery slope: Oviedo Art 13 and UNESCO 1997 bar heritable non-therapeutic modification; He Jiankui 2018 CRISPR case shows incremental erosion; sex is the gateway to trait design. Comparative: UK HFE Act 2008, Canada AHR Act 2004 s.5 (criminal), Oviedo Art 14 - convergent prohibition with a medical exception. Conclusion (~70 words): permit selection only to avoid serious sex-linked disease; otherwise the harms to equality, dignity and medical integrity outweigh a private preference.
The model essay
The question must first be split in two. Selecting a child's sex to avoid a serious sex-linked disease, such as haemophilia, is medicine, and few object to it. The contested case is non-medical selection driven by preference or cultural pressure. Reproductive liberty is a real and weighty freedom, but it is not unlimited; it is bounded, like every liberty, by harm to others, by the dignity of the child, and by equality. Tested against those bounds, non-medical sex selection should not be permitted.
The first objection is demographic. The natural sex ratio at birth is roughly 105 boys to 100 girls, yet in societies with strong son preference, China and parts of India have pushed it above 110, and the United Nations Population Fund estimates around 142 million women and girls are "missing" from the world's population as a result of sex selection and related practices. These are not the product of malice but of millions of private, individually rational choices, which is precisely the point: aggregated, they corrode the equality of an entire generation. On Mill's own harm principle, autonomy ends where it inflicts serious harm on others, and a distortion of this scale qualifies. The reply that a balanced, regulated society would avoid imbalance underestimates how quickly cultural preference drives skew and overestimates a regulator's ability to police private motives at scale.
Even if the demographic risk could be neutralised, a deeper objection remains. To specify a child's sex is to shift procreation from acceptance toward manufacture. Michael Sandel argues in The Case Against Perfection that designing children expresses a "drive to mastery" that erodes the openness to the unbidden which lies at the heart of parental love; in Kantian terms, the child is treated partly as a means to the parents' preference rather than as an end. The retort that parents already choose schools, diets and IVF confuses nurture with identity. Shaping the environment a child grows up in differs in kind from fixing who that child is before they exist.
The choice is also never neutral. To prefer a sex is to act on a belief about what that sex will be like, reviving the idea that gender is destiny. This is why CEDAW's Joint General Recommendation No. 31 (2014) classifies prenatal sex selection as a harmful practice rooted in son preference and the disempowerment of women. Even "family balancing", choosing a girl to complete a set of boys, affirms that sex is a thing worth ranking and selecting, which is the very assumption equality should dismantle.
Finally, sex selection normalises the logic of designing children. It is the first, most discrete step on a path toward selecting height, appearance or intelligence. The Oviedo Convention bars heritable genetic modification for non-therapeutic ends (Article 13), as does UNESCO's 1997 Universal Declaration on the Human Genome, and the 2018 case of He Jiankui, who gene-edited embryos and received a three-year prison sentence in China, shows how rapidly "innovation" slides into eugenic violation once medicine moves from healing to tailoring. Holding the line at sex is easier than holding it later.
The law has reached this conclusion across jurisdictions. The UK's Human Fertilisation and Embryology Act 2008 prohibits sex selection except for serious medical reasons; Canada's Assisted Human Reproduction Act 2004 makes non-medical sex selection a criminal offence; and Article 14 of the Council of Europe's Oviedo Convention forbids it save to avoid serious hereditary sex-related disease. That three independent systems drew the same line, with the same medical exception, suggests a considered moral judgement rather than mere squeamishness. People should be free to use sex selection to spare a child a grave inherited illness. Beyond that, the costs to equality, dignity and the integrity of medicine are too high, and the answer is no.
Authorities worth knowing
Human Fertilisation and Embryology Act 2008, Schedule 2
2008 c. 22 (United Kingdom)
A licence cannot authorise practices designed to secure that a child will be of one sex rather than another, except where there is a particular risk of a serious gender-related (sex-linked) medical condition; non-medical sex selection is prohibited.
Assisted Human Reproduction Act, s 5
SC 2004, c 2 (Canada)
It is a criminal offence to perform any procedure or provide any treatment to ensure or increase the probability that an embryo will be of a particular sex, except to prevent, diagnose or treat a sex-linked disorder or disease.
Convention on Human Rights and Biomedicine (Oviedo Convention), Articles 13 and 14
ETS No. 164 (Council of Europe, opened for signature 4 April 1997)
Article 14 forbids using techniques of medically assisted procreation to choose a child's sex except to avoid serious hereditary sex-related disease; Article 13 limits interventions on the human genome to preventive, diagnostic or therapeutic aims and bars heritable modification.
CEDAW Joint General Recommendation No. 31 / CRC General Comment No. 18 on harmful practices
CEDAW/C/GC/31-CRC/C/GC/18 (14 November 2014)
Prenatal sex selection is identified as a harmful practice grounded in son preference and the social and legal disempowerment of women, which States Parties are obliged to eliminate.
UNESCO Universal Declaration on the Human Genome and Human Rights
UNESCO General Conference, 11 November 1997 (endorsed by UNGA Res 53/152, 1998)
Practices contrary to human dignity, such as germline interventions and reproductive cloning, are not permitted; the human genome is the heritage of humanity and may not give rise to financial gain or eugenic selection.
How the law frames it
United Kingdom
The Human Fertilisation and Embryology Act 2008 (amending the 1990 Act) puts the long-standing HFEA policy into statute: a licence cannot authorise embryo testing or sperm processing intended to select a child's sex unless there is a particular risk of a serious sex-linked medical condition. Non-medical sex selection is therefore unlawful in the UK, while medical selection to avoid disease is permitted. The UK has not signed or ratified the Oviedo Convention, regarding it as too restrictive on embryo research, so it reaches the same prohibition on sex selection by its own domestic route.
Canada
Canada goes furthest: section 5 of the Assisted Human Reproduction Act 2004 makes it a criminal offence, punishable by imprisonment, to perform any procedure to ensure or increase the probability that an embryo will be of a particular sex, except to prevent, diagnose or treat a sex-linked disorder or disease. Sex selection for preference or family balancing is thus not merely unfunded or discouraged in Canada but prosecutable.
ECHR
The Council of Europe's Oviedo Convention (1997) addresses this directly: Article 14 forbids using medically assisted procreation to choose a future child's sex except to avoid serious hereditary sex-related disease, and Article 13 confines genome interventions to therapeutic ends and bars heritable modification. Although not every Council of Europe state has ratified Oviedo (the UK has not), it is the clearest pan-European statement of the principle, and the European Convention's own protections of private and family life (Article 8) are read alongside, not against, these bioethical limits.
Counter-arguments and how to defeat them
Counter. Reproductive decisions are private and self-regarding, so the state has no business prohibiting sex selection between consenting parents.
Rebuttal. Mill's harm principle, the very basis of that liberty, also limits it. Sex selection is not purely self-regarding: aggregated across a population it skews sex ratios (the UNFPA's ~142 million missing women), and it expresses a judgement about the worth of a sex that affects the wider community's equality. Where a private choice produces public injustice, regulation is justified.
Counter. Parents already make countless choices, including IVF, screening and abortion, so adding sex is just one more responsible decision.
Rebuttal. There is a difference in kind between shaping the environment a child grows up in and fixing the child's identity before they exist. Choosing a school is nurture; choosing a sex is design. The continuum argument proves too much: it would equally license selecting height or intelligence, which is exactly the trajectory the objection ignores.
Counter. In a balanced, well-regulated society the demographic risk is negligible because preferences would cancel out.
Rebuttal. This is speculative against a documented history of rapid skew wherever son preference exists. Regulation cannot anticipate or police millions of private motives, and even balanced uptake (girls to balance boys and vice versa) still entrenches the assumption that sex is something to be ranked and selected, which CEDAW identifies as a harmful practice.
Counter. Sex is a discrete, binary trait, so permitting its selection does not logically entail designer babies.
Rebuttal. Ethical boundaries erode incrementally, not logically. Normalising the choice of one fixed trait shifts the default from acceptance to selection, weakening resistance to the next step. The He Jiankui CRISPR case and the express bans in Oviedo (Article 13) and the UNESCO Declaration exist precisely because the line, once crossed, is hard to redraw.
Conclusion
Reproductive liberty deserves real respect, but it is bounded by harm, dignity and equality, and non-medical sex selection breaches all three. It risks demographic distortion on the scale the UNFPA documents, it commodifies the child by turning procreation into specification, it entrenches the gender stereotyping that CEDAW treats as a harmful practice, and it normalises the wider logic of genetic design that Oviedo, UNESCO and the He Jiankui case warn against. The convergent prohibitions in the UK, Canada and the Oviedo Convention, each preserving a medical exception, mark the right line. People should be free to select against a serious sex-linked disease; they should not be free to choose a child's sex by preference.
Evidence you can cite
- The natural human sex ratio at birth is approximately 105 boys per 100 girls; values persistently above this range indicate sex-selective practices.Our World in Data, Sex Ratio at Birth (drawing on UN World Population Prospects) — source
- China and parts of India have recorded sex ratios at birth well above 110 boys per 100 girls, reflecting sex selection rather than biological variation.Our World in Data, Sex Ratio at Birth; Pew Research Center — source
- An estimated 142.6 million women and girls were "missing" from the global population as of 2020 as a result of sex selection and excess female mortality, with China and India accounting for the large majority.UNFPA, State of World Population 2020 (Against My Will) — source
- He Jiankui, who created gene-edited babies announced in 2018, was sentenced in December 2019 to three years in prison and fined 3 million yuan for illegal medical practice.CNN / Science (AAAS) reporting on the Shenzhen Nanshan District People's Court judgment — source
Further reading
- Michael J. Sandel, The Case Against Perfection (2007) - the "drive to mastery" critique of designing children.
- UNFPA, State of World Population 2020 (Against My Will) - the data on gender-biased sex selection and "missing women".
- CEDAW/CRC Joint General Recommendation No. 31 / General Comment No. 18 (2014) - sex selection as a harmful practice.
- Convention on Human Rights and Biomedicine (Oviedo Convention), Articles 13 and 14 - the European bioethical standard.
- Human Fertilisation and Embryology Act 2008 and Assisted Human Reproduction Act 2004 (Canada) - the UK and Canadian statutory lines.