Oestrogen in Men

Oestrogen is the female hormone and testosterone the male hormone. Right? To a point, yes. Oestrogen is present in biologically female bodies to a much higher extent than biologically male bodies and testosterone is the predominant male hormone. But both hormones are also found in both genders.

To think of oestrogen as only female and testosterone as only male is arguably as outdated as ‘pink’ and ‘blue’ jobs. Testosterone replacement is becoming as much a part of hormone replacement therapy for the female menopause as oestrogen replacement. And the role of oestrogen in the male body is also now much more understood.

In a female body, oestrogen, along with progesterone, is responsible for regulating the female reproductive system. It has an influence over everything from the onset of puberty and periods to the perimenopause and eventual menopause. Oestrogen also influences a woman’s mental health as well as cardiovascular and bone health.

Testosterone levels in a male body begin to rise sharply during puberty and is responsible for typically ‘masculine’ characteristics. These include the development of facial and body hair, a deep voice, behavioural traits such as competitiveness and aggression, faster fat metabolism and higher muscle mass and strength. It’s also responsible for the growth of the penis and testicles during puberty and consequently, sexual urges and activity.

In fact, it had previously been posited that an inability to achieve orgasm through “enough penetrative thrusting through intercourse to simulate the clitoris” was a sign of female sexual dysfunction. Thrusting?

But what about the role of oestrogen in males?

The most predominant form of oestrogen in a male body, called oestradiol, is critical for male sexual function. Testosterone plays the most significant role in male sexual function but oestradiol is also crucial and needs to stay within the right balance with testosterone in order for a male to achieve and maintain an erection, maintain his libido and to produce sperm. ^[1]

The male brain also has oestrogen receptors that function to attract oestrogen which then binds to these receptors and controls emotional and cognitive function such as memory and concentration.

Although more commonly associated with female bodies, oestrogen does also play a role in the health of the hair, skin and nails in both females and males, which is important for both the physical health of these systems, as well as emotional health in terms of self-esteem and confidence.

The male menopause is a phrase often used to describe the andropause – the period of time in a man’s life where his hormones begin to change. However, using the phase ‘male menopause’ is unhelpful, as it suggests that it’s the same as the actual menopause that females experience – when it isn’t.

Whilst it’s true that testosterone begins to decline as a man ages, this decline is nowhere near as steep as that of oestrogen in women, and as such, doesn’t have the same level of often dramatic and unpredictable effects and symptoms. In a female body, a fast decline in oestrogen results in a loss of fertility as well as typical menopause symptoms including mood swings, night sweats, hot flushes, insomnia, fatigue and brain fog. But in a male body, a slow decline in testosterone doesn’t necessarily mean a loss of fertility. We all know the media tales of octogenarian men fathering children, after all.

In a male body, as testosterone gradually decreases, the oestrogen concentration increases. As yet it’s not fully understood if this is because oestrogen actually does rise, or because it becomes more dominant as testosterone levels decline.

Although oestrogen supports male sexual function and fertility, if levels are too high, whilst testosterone levels are too low, it can result in erectile dysfunction, a lowered sperm count and gynecomastia – the development of fatty tissues in the breasts of men.

High oestrogen levels can also result in a lowered sex drive, loss of muscle mass and bone density, insomnia, fatigue, hair loss and a shrinking of the penis and testicles ^[2]. It can also lead to a low mood and depression. ^[3]

So whilst the andropause doesn’t necessarily mean an end to a man’s fertile years, like the menopause it can cause unpleasant physical and emotional symptoms. If you or your partner are concerned about symptoms of the andropause, speak to your GP who can discuss the possibly of hormone replacement therapies with you

In a male body, oestrogen is primarily produced by the testes and the brain. In particular, it’s produced by the Leydig cells located within the testes. ^[4] Leydig cells are the primary source of testosterone in males, meaning that these cells are largely responsible for the production of sperm, sexual development and desire and the development of male sexual characteristics and biology during puberty. ^[5]

This means that oestrogen concentrations are particularly high in semen, the fluid produced by the testes that contains sperm and makes up the ejaculate. ^[6]

But that’s not the full story. Oestrogen is also produced in male bodies by the action of an enzyme called aromatase. Aromatase converts some of the testosterone circulating around a male body into oestrogen, an action that takes place in the brain… ^[7]

Yes. Very much so. Oestrogen in the most part is produced by the ovaries in a woman’s body. But emerging evidence suggests that oestrogen is also produced by the female brain, ^[8] and we’ve argued before that this is evidence enough change the way we approach treatments for menopause symptoms, in part, normalising the importance of the female orgasm.

That fact that oestrogen in males is also produced by the brain as well as the testes further supports the evidence that it isn’t just the ovaries that are responsible for oestrogen production.

Professor Ei Terasawa at the Wisconsin National Primate Research Centre at the University of Wisconsin-Madison is spearheading the way when it comes to proving that the brain produces oestrogen. Professor Terasawa’s team, supported by Brian Kenealy PhD, performed various different experiments on rhesus monkeys who are considered to have very similar reproductive, immune and neurological systems to humans.

The results led to the team concluding, "These findings not only shift the concept of how reproductive function and behaviour is regulated but have real implications for understanding and treating a number of diseases and disorders." ^[8]

It therefore stands to reason, that one of these conditions could well be, and should well be, the menopause. And possibly even the andropause. And whilst this article is primarily focussed on the role of oestrogen in men, we’ve cleverly used it to point out the importance of understanding the role of oestrogen in women.

Perimenopausal, menopausal and post-menopausal women have naturally lowered levels of oestrogen. The fact that it can be produced by the brain, coupled with the fact that science also proves that oestrogen is produced by the brain during the female orgasm, ^[9] only further supports the importance of women taking charge of their orgasms.

At Emotional Bliss, that’s exactly what we’re about. Women taking control, normalising the importance of pleasure and orgasm and using the right intimate massager to do just that.

^[1] Schulster, M., Bernie, A. M., & Ramasamy, R. (2016). The role of oestradiol in male reproductive function. Asian journal of andrology, 18(3), 435–440. https://doi.org/10.4103/1008-682X.173932

^[2] Vandenput, L., & Ohlsson, C. (2009). Estrogens as regulators of bone health in men. Nature reviews. Endocrinology, 5(8), 437–443. https://doi.org/10.1038/nrendo.2009.112

^[3] Stanikova, D., Luck, T., Bae, Y. J., Thiery, J., Ceglarek, U., Engel, C., Enzenbach, C., Wirkner, K., Stanik, J., Kratzsch, J., & Riedel-Heller, S. G. (2018). Increased oestrogen level can be associated with depression in males. Psychoneuroendocrinology, 87, 196–203. https://doi.org/10.1016/j.psyneuen.2017.10.025 .

^[4] Hess R. A. (2003). Oestrogen in the adult male reproductive tract: a review. Reproductive biology and endocrinology: RB&E, 1, 52. https://doi.org/10.1186/1477-7827-1-52

^[5] Aladamat N, Tadi P. Histology, Leydig Cells. [Updated 2021 Nov 19]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK556007/

^[6] Hess, R. A., Bunick, D., Lee, K. H., Bahr, J., Taylor, J. A., Korach, K. S., & Lubahn, D. B. (1997). A role for oestrogens in the male reproductive system. Nature, 390(6659), 509–512. https://doi.org/10.1038/37352

^[7] Wu, M. V., Manoli, D. S., Fraser, E. J., Coats, J. K., Tollkuhn, J., Honda, S., Harada, N., & Shah, N. M. (2009). Estrogen masculinizes neural pathways and sex-specific behaviors. Cell, 139(1), 61–72. https://doi.org/10.1016/j.cell.2009.07.036

^[8] Kenealy, B. P., Kapoor, A., Guerriero, K. A., Keen, K. L., Garcia, J. P., Kurian, J. R., Ziegler, T. E., & Terasawa, E. (2013). Neuroestradiol in the hypothalamus contributes to the regulation of gonadotropin releasing hormone release. The Journal of neuroscience: the official journal of the Society for Neuroscience, 33(49), 19051–19059. https://www.ncbi.nlm.nih.gov/books/NBK556007/

^[9] van Anders, S. M., Brotto, L., Farrell, J., & Yule, M. (2009). Associations among physiological and subjective sexual response, sexual desire, and salivary steroid hormones in healthy premenopausal women. The journal of sexual medicine, 6(3), 739–751