I Changed My Sex, and So Can You
Content Warning: Potential gender dysphoria-inducing language, heavy discussion of sex characteristics, clinical and scientific language. I identify as transsexual rather than transgender, as my gender identity has always remained the same; I changed my sex to match it. I am a firm believer that people can change their sex, but I don’t tell everyone that right away. If I deem it worth my time, I explain it. In every way that matters, we definitely can. And what cannot be changed isn’t visible to the eye, or isn’t even a characteristic that everyone has in the first place. Humans aren't anywhere near as sexually dimorphous as transphobes want us to think. For example, we all have nipples for a reason. Furthermore, the gonads and genitals of the typical male and female are entirely analogous structures.
There are many characteristics of sex. Primary and secondary. Genitals, gonads, gametes, chromosomes, hormones, and characteristics developed after puberty (such as increased breast size, broadening of the hips or shoulders, fat distribution, percentages of fat and muscle, body and facial hair, and lowered voice).
Genitals can be changed. Vaginoplasty and phalloplasty have had ~100 years to advance, and today there are multiple techniques and results to choose from. Metoidioplasty is relatively newer but has considerably fewer surgical risks when compared to phalloplasty. Not only that, but HRT, on its own, changes the genitalia in significant ways. The penis and testicles get smaller and softer, and one can achieve orgasm without an erection. The clitoris grows (in some lucky cases, up to 3 inches in length) and resembles a micro-penis.
Chromosomes, gonads, and gametes cannot be changed. However, these characteristics cannot be seen, and they do not necessarily define your gender OR your sex. Not every woman assigned (or observed, or designated) female at birth has XX chromosomes, ovaries, and eggs. Not every man assigned male at birth has XY chromosomes, testes, and produces sperm. Intersex people exist. As do infertile people.
Additionally, many trans men on testosterone see a menstrual cycle cessation, and many trans women on oestrogen (and/or progesterone) experience monthly PMS symptoms.
Hormones can be changed. After being on hormone replacement therapy (HRT) for long enough, one stops producing the "wrong" hormones, and one's body begins to rely on the introduced hormones. The testosterone, oestrogen, and progesterone used in modern HRT are biologically identical to the hormones endogenously produced in the body.
Secondary sex characteristics can be changed with OR without surgery. During the first ~5 years of cross-sex HRT, a transgender person experiences everything a pubertal cisgender person of their identified gender experiences. In addition, the secondary characteristics of one's first puberty are minimised, and can even be partially reversed.
The breast tissue of trans men often becomes less dense, and fat redistribution can lead to a noticeable decrease in chest size as well.
The introduction of progesterone to oestrogen-based gender transition has shown a greater increase in breast size (even cis women who start taking progesterone as birth control after puberty are known to notice their breasts getting bigger).
Most significantly, after many years, the pelvis narrows (with testosterone) or widens (with oestrogen) accordingly and shifts in angle.
Unfortunately, a significant increase in height is not expected after the growth plates of one's bones are fused. However, some trans women have reported a decrease in height along with shoe size.
To conclude, every person has the ability to develop any secondary sex characteristic (including lactation), once the code in their genes is switched on by the required hormone(s).
