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An Anatomist examines Sex and Gender

As a woman who has spent my life in Surgery and STEM since obtaining my medical degree in the nineties, I have watched the debate surrounding sex and gender for some time. These fields have traditionally been challenging ones for women to succeed in, and sadly continue to be so (Hu et al., 2019; Roper, 2019; Richter et al., 2020; Larson, 2021). While I have not hidden my views about sex and gender issues in the past, I felt moved to write more publicly due to the Criminal Justice Bill that is going through the Oireachtas here in Ireland. The wording in this Bill leaves me with no clarity as to what gender is any more in Irish law, given the new definition which states that “‘Gender’ means the gender of a person or the gender which a person expresses as the person’s preferred gender or with which the person identifies and includes transgender and a gender other than those of male and female” (Criminal Justice Bill, 2022; Salach, 2023). Given the potential for conflation and confusion between sex and gender-based issues, both of which merit attention, my personal preference is to limit the use of male and female to sex-based issues, although I recognise that male and female are traditionally and currently used for gender-based literature and legislation, which I will return to in due course.

Both biological and sociological factors are relevant to individuals and societies and this confusion in nomenclature does no service to either. This is not an academic issue confined to theoretical debate, or the etiquette of personal interactions, but has broader societal, healthcare and criminal consequences in many jurisdictions, and we cannot meaningfully discuss what we cannot define. Confusion in social and scientific discourse has increased over the past two decades in differentiating sex and gender, with the two terms being seen by some as synonymous and interchangeable, while others make a distinction between the two, so as to be precise in their discourse (Torgrimson and Minson, 2005; Heidari et al., 2016; Madsen et al., 2017; Cavanagh, 2019; Greaves and Ritz, 2022).

To my mind a straightforward definition or distinction is that “sex is biologically determined and gender is culturally determined” (Torgrimson and Minson, 2005). The terms male and female are traditionally used to describe organisms (or male and female parts of plants or flowers) according to their role in sexual reproduction, and the manner in which sex is biologically determined varies considerably across domains, even within the animal kingdom alone (Hake and O’Connor, 2008; Charlesworth and Mank, 2010; Heidari, et al., 2016). For reptiles such as crocodile or turtles, sex is determined by the warmth of the egg during its incubation (Crews, 1996; Quinn, 2007; Bhattacharjee et al., 2022). The sex of birds is determined by the inheritance of sex chromosomes; if a chick embryo has ZW sex chromosomes it grows into a hen, if it has ZZ it grows into a rooster (Smith and Sinclair, 2004). Placental mammals typically have XX or XY chromosomes for females and males respectively, and monotremes have multiple pairs of sex chromosomes, bearing some resemblance to chromosomes of both birds and placental mammals (Smith and Sinclair, 2004; Rens et al., 2007).  Just as individuals may be born with congenital conditions of the cardiovascular or gastrointestinal systems, so too individuals may be born with congenital anomalies of the reproductive system (Corsello and Giuffrè, 2012). Nomenclature and definitions of “congenital conditions in which development of chromosomal, gonadal, or anatomic sex is atypical” have undergone many revisions and there is still no universal consensus on terminology (Lee et al., 2006; Cools et al., 2018; Griffiths, 2018). Still, I would opine that in mammals, sex is biologically determined, develops in utero and is thereafter immutable after birth, notwithstanding that a small number of individuals are born with challenging congenital conditions, requiring specialist investigation, diagnosis and support.

So then what of gender? Is it biological form or psychological identity? It is fixed or fluid? Potential definitions are that “gender is culturally determined” or alternatively “socially constructed roles, behaviours and identities of female, male and gender-diverse people” (Torgrimson and Minson, 2005; Heidari, et al., 2016). Our recent Citizen’s Assembly on Gender Equality specified in their report that “for the purposes of this consultation, please understand ‘gender’ to refer to any and all options in terms of gender identity.” (Citizens’ Assembly on Gender Equality, 2021). The even more recent Junior Cycle Social, Personal and Health Education (SPHE) also makes reference to “gender identity” (NCCA, 2023). However, while both sex and gender were seen interchangeably in the past and both traditionally (and currently) use the terms male and female, biological sex is distinct from psychological identity, and the use of identical terms for both has given rise to calls for clarity between sex and gender (Heidari, et al., 2016; Madsen, et al., 2017). Throughout history there have been examples of males and females who did not conform to societal or cultural roles. In Ireland we have tales of Queen Medb, of Grace O’Malley and Irish Surgeon James Barry, all of whom were biological females; two of them were recognisably gender non-conforming women, while James Barry was taken to be a man until after death. When the conflation of biological sex and gender identity occurs conversationally, confusion may arise. When documented in research and healthcare, suboptimal outcomes or errors may occur (Heidari, et al., 2016; Madsen, et al., 2017). When enshrined in law, legal loopholes, liabilities and lawfare may ensue. Sex-based rights and single-sex spaces may be eroded or eradicated, with adverse consequences for the vulnerable (Parveen, 2018; Biggs, 2020; Freedman et al., 2020; HC 884, 2020).

Irish legislation has previously defined gender as binary; the Irish Equality Act uses the term “gender”, wherein individuals are either male or female (Equality Act [Ireland], 2004). The Irish Gender Recognition Act  then allowed people to legally change their self-identified gender by signing a solemn declaration and “provides that a gender recognition certificate has effect that if the preferred gender is the male gender, the person’s sex becomes that of a man, and if the female gender, the person’s sex becomes that of a woman” (Department of Social Protection; Gender Recognition Act [Ireland], 2015). While the Bill was originally drafted as a medical model, this was altered to self-identification as the Bill went through the final committee stage in our Oireachtas, just prior to its eventual enactment. Anyone who wishes to be identified as female under law may now do so, by the simple signing of this form, and be legally protected from any questioning or criticism of their (self-identified) gender under our Equality Act (Equality Act [Ireland], 2004). In contrast, UK legislation is far clearer and specifies sexsexual orientation and gender reassignment to all be separate, but equally protected, characteristics (Equality Act [UK], 2010). What are the consequences of current and proposed legislation for sex-based rights, sex-based discrimination, or single-sex spaces in Ireland? We have seen that criminal convictions, including those for violent or sexual offences, have no bearing or bar on the “right” of an individual born male, with no medical or surgical transition, to self-identify as female and to thereafter be incarcerated among women (Raleigh, 2023).

We are now facing a new Criminal Justice Bill which states that “‘Gender’ means the gender of a person or the gender which a person expresses as the person’s preferred gender or with which the person identifies and includes transgender and a gender other than those of male and female” (Criminal Justice Bill, 2022; Salach, 2023).

It’s a circular argument. Gender is defined as gender. If the Criminal Justice Bill is enacted in its present form, possession (not use, possession) of any materials deemed potentially offensive to anyone’s (self-identified and potentially self-defined) gender may become a criminal offence and punishable by a fine and / or imprisonment.  Perhaps an outré opinion from an anatomist insisting that females do not have a penis will become a crime, punishable by law. So, I am writing this opinion piece before the articulation of a belief in the immutability of physical sex is potentially a punishable and imprisonable offence, the criminality of such a belief being determined solely by any (unknown and untargeted) person being subjectively offended by it. The trajectory of Irish legislation is seemingly to erase sex and sex-based issues from law and the constitution, to be replaced by gender – with no clear definition of what gender means. The denial of the physical reality of bodies, with the innate and immutable anatomical and physiological differences that are specific to the male and female sexes, is reactionary and regressive. Irrespective of anyone’s views on what is an increasing (and increasingly controversial) issue (Cass, 2022a; 2022b; Block, 2023), the needs and lived experiences of those whose gender identity and physical natal sex remain in alignment will differ from any who transition; socially, psychologically, and medically (Goldstein et al., 2017; Greaves and Ritz, 2022). We need clear definitions that distinguish between the physical and the psychological to recognise, discuss and manage these needs. I would rather assert and attest that physical and physiological differences exist between males and females and that while psychological identity may be fluid, physical sex is inherently immutable. Whether it becomes a criminal offence or not.


Jane Holland, MD, PhD, MRCSI, is a Senior Lecturer in Anatomy. This article first appeared on Genspect here and is republished by Gript with permission



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