Not a Choice: Understand the paths to sexual development and gender identity

If you are asking why you or someone else is lesbian, gay, bisexual, transgender or transsexual, queer or questioning, or intersex, yes, there are answers. And it’s not a choice. Many of the answers are set in our brains. Let’s see how we get there.

We all are created by the same processes. We all deserve respect.

We all have learned that people, as well as other mammals, have a set of chromosomes comprised of genes that make us who we are. We have been taught that these include two chromosomes to determine our sex: male versus female. In humans and most mammals, these have been named X and Y. Most of us are familiar with the idea that we each possess two sex chromosomes, that a female has two Xs (XX), and that a male has an X and a Y (XY).

What is not widely known, but has been written about for over thirty years, is that:

  • We don’t all have just two sex chromosomes.
  • Certain brain structures differentiate between male and female.
  • Absent a Y chromosome, anatomical and brain development generally proceed as female.
  • Presence of a Y chromosome generally pushes anatomical and brain development toward male. This is due to its kickstarting the production of male hormones in early stages of the embryo.
  • Almost no-one’s brain development is fully and exclusively either male or female. This makes sense in light of the fact that females produce a larger amount of female hormones and a smaller amount of male hormones, and that males produce a larger amount of male hormones and a smaller amount of female hormones.
  • Over the past few decades, research has identified an increasing number of brain structures and areas within them that are associated with aspects of maleness and femaleness, including gender identity and sexual preference.
  • Internal sexual organs, external sexual anatomy, and various sexually-differentiated areas of the brain all develop within the fetus at different points in time.
  • Fetal development of both sexual anatomy and sexually-differentiating brain structures is influenced by a combination of genetics, sex chromosomes, sex hormones, drugs administered to the mother during pregnancy, and environmental chemicals to which the developing fetus is exposed.
  • This development of anatomy and brain structure – subject to the influences of genetics, hormones, drugs, and chemicals – occurs on a continuum rather than on a female versus male coin-flip.
  • The influences just mentioned are time-sensitive, with different aspects of anatomy and brain areas developing at different points in fetal development. This allows for a mosaic mix of both female- and male-differentiated structures in both anatomy and brain development.
  • Inconsistent exposure to hormones, drugs, and chemicals throughout fetal development presents opportunity for complex combinations of the different aspects of sexual development and identity. This means:
    • Anatomy can develop in one direction and brain structures in the other.
    • That internal sexual organs and external sexual anatomy can develop in sexual opposition to one another.
    • Brain structures that affect gender identity or sexual preference can develop in opposition to sexual anatomy, sex chromosomes, or each other.
  • These facts explain the non-binary aspect of sexual development, including internal and external sexual anatomy, sexual preference, and gender identity. Various aspects of sexual development may occur with non-binary combinations or ambiguities. All of these can and do develop on a continuum.

The material presented on this site is a distillation of much research – research by those doctors and scientists who made the discoveries, by others who sifted through reams of research findings to compile their own works, and by my searching, finding, and assembling it in Not a Choice. To provide a concept of the work and brainpower involved, and its legitimacy, this site’s References page lists the sources from which this information was garnered. This includes research publications provided by the illustrious National Institutes of Health (NIH) and by the Head of the Laboratory for Neuropsychiatric Disorders of the Netherlands Institute for Neuroscience, among numerous others.

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For further information . . .

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