To start understanding the complexities of sex it is necessary to establish some background to the biology of sex determination. What is male and female? It’s a chromosome thing right? Well in a sense, yes.

To categorise male and female based on the presence or absence of a Y chromosome would be just a part of the bigger picture. What about the chromosomal trisomies XXY and XYY?

Also, and perhaps more significantly ‘In Swyer syndrome, individuals that are XY (the pattern typically found in males) have female reproductive structures’. People with Swyer syndrome are typically raised as girls and have a female gender identity [1].

Even within the definition of ‘chromosomal sex’ there are subtleties that need to be considered,

What is it within the chromosomes that dictate sex? The sex-determining SRY gene is found on the Y chromosome and it leads to the development of male phenotypes, such as testes[2]. Sometimes however, the SRY gene can go wandering and find itself in an X chromosome (translocation)

......this can result in an individual that is XX, the pattern normally found in females, having male appearance. So, even at the level of the gene, sex is not straightforward.

What of the hormones that dictate sex – the androgens? You will not be surprised to learn that things get no simpler at the endocrine level. Androgen sensitivity syndrome is a condition where the individual has faulty receptors on the cells that would otherwise be...….

‘switched on’ by the male sex hormone, testosterone. As a result, the person has some, or all of the physical traits of a woman, but the genetic and chromosomal make-up of a man (XY).

Sex is not the binary, uncomplicated label that we are awarded at birth. We have no idea of the chromosomal, genetic and hormonal intricacies that lie beneath our skin. It may not be possible to translate these complexities within our lessons, however...

... it might be possible to engage our students with the idea that sex is complex and no doubt more complex than those who judge, might believe. If we can do that then we have educated….

What is the difference between ‘sex’ and ‘gender’? Sex and gender are NOT synonyms – the words have different meanings and should be used precisely in our teaching in order to avoid misconceptions and microaggressions

Sex is the classification of a person as male, female, or intersex. When we are born, doctors usually decide whether female or male will be listed on our birth certificate.

This sex assignment at birth is typically based solely on one’s genitals, however sex characteristics, as we have learned, also include chromosomes, gonads, and sex hormones. Our sex assigned at birth may or may not correspond to our gender.

Gender describes our internal understanding and experience of our own gender identity. Each person’s experience of their gender identity is unique and personal and cannot be known simply by looking at a person [3].

We must not be afraid to use the term sex when teaching biology, it is a necessary descriptor of anatomy across nature; what is important is to be mindful of the differences and nuance in definition.

If somebody identifies as a male, regardless of birth assignment, regardless of anything, they are male. Issues arise as the descriptor of sex and gender are the same. We must be mindful of this when we use the terms male and female as they describe both sex and gender.

Can I use the term male and female? Yes. Of course, you can refer to male and female reproductive organs and sex hormones. To avoid teaching this, leads our children towards not understanding anatomy and endocrine control.

What is important is not to link sexual development to gender. For instance, if we are teaching the menstrual cycle we must be careful not to say that menstruation is a solely female process.

This might seem incongruous, but it is an important distinction to make. Since we use male and female to describe gender it is therefore factually incorrect to say that only women menstruate as many transgender men may also menstruate. We must also....

...consider the non-binary community, some of whom will menstruate but not identify as a woman. If we are viewing this from the point of view of sex then clearly the statement stands up to rigour, but the students listening have no idea whether we are referring to gender or sex.

It is also true to say that transgender women will not menstruate, so let us not additionally isolate women who may also be, for example, post-menopausal or have a medical condition, with statements like ‘all women menstruate’

At this point you may wonder how you will teach year 8s about the menstrual cycle. I am not suggesting that you avoid the issue or indeed tackle it head on, it might though be a good opportunity, depending on the class, to introduce the idea of sex and gender.

You may want to use the term cis- female (which refers to someone that identifies as a woman and was assigned as female at birth). However you chose to approach this subject please always be mindful of the young minds before us.

Whether it is a wonderful opportunity to make a student feel understood or included or to not miss an opportunity to expand the minds of others – that is after all why we are here.

[1] https://ghr.nlm.nih.gov/condition/swyer-syndrome [Accessed 9/6/2020]
[2] https://embryo.asu.edu/pages/sex-determining-region-y-mammals [Accessed 9/6/20]
[3] https://www.thetrevorproject.org/wp-content/uploads/2020/03/Guide-to-Being-an-Ally-to-Transgender-and-Nonbinary-Youth.pdf [Accessed 9/6/2020]