- Menopause happens the same way it always has: what is changing is what science is only beginning to understand about it.
- Today it is understood as a neuroendocrine transition, from the reproductive stage to the post-reproductive one: it is not only the ovaries that change, the brain does too.
- Strictly speaking, the word “menopause” is a single day: the day of your last period.
- Women can live more than a third of our lives after we stop reproducing. Very few mammal species have a stage like this.
- Understanding this process helps you see your body with more compassion and patience, and talk better with health professionals.
The process toward menopause is being redefined. Not because the way it happens in our bodies is changing, of course not: it has always happened exactly the same way. What is being redefined is what we didn't know before, because there haven't been enough studies or enough interest to understand it well.
Until a few decades ago, the transition to menopause was considered the end of reproductive life: the ovaries stopped ovulating and the woman stopped menstruating. As simple as that, as if a woman's body were that simple. Today it is being redefined as a neuroendocrine transition of a woman's body, from the reproductive stage to the post-reproductive one. Although, strictly speaking and officially all over the world as of today, the word “menopause” is a single day: the day of your last period.
It is neuroendocrine (brain + hormones) because, besides the ovaries no longer ovulating, the brain reconfigures the way it communicated with the rest of the body through the hormones from the ovaries. By the time we reach this stage, the brain and the ovaries have been talking for forty years. Every month the brain asks and the ovary answers, without missing a single time. And the answer isn't said in private: it is said out loud, in the blood, where the whole body hears it. That's why, when that answer starts to fail, it isn't only the brain that finds out — the whole house finds out. Month after month, eggs, ovaries, hormones, uterus and endometrium coordinate, almost always with the precision of synchronized swimming, preparing the body to have a baby. For nature, reproduction is the most important thing.
And even so, women can live more than a third of our lives after we stop reproducing. We are one of the very few mammal species with a stage like this: we share it with a few species of whales, like orcas. In almost every other species, life lasts practically as long as its reproductive life.
Women
Almost every other species
Diagram, not to exact scale. Orcas and a few other whales also have this stage. Sources: Lumsden and Sassarini, 2019; Ellis et al., 2018.
So our brain has to swap that predominant communication, which will no longer be the main one, for a new one: that of a woman who has retired from her reproductive life. The brain is freed from having to prepare the body for a baby every month, and it has to adapt to much less hormone, and to another one that takes over, to communicate from now on with the rest of the body.
Not all of us reach this stage by the same path. If both of your ovaries were removed in surgery, or if chemotherapy or a medication switched them off, that conversation doesn't fade little by little: it is cut off all at once. And if your uterus was removed but your ovaries were left, the conversation goes on just as before; what you lose is the period you use to keep count. We explain it in Perimenopause and menopause: what changes in your hormones.
If you'll allow me an opinion: I think evolution never cared about our symptoms at 45, because what happens to us after reproductive age barely changes how many children we leave behind. On top of that, today we live in an environment very different from the one in which this body was formed, and many more women get to live through this whole stage. Nature wasn't going to solve this. Medicine could, and that's why we have to demand that it help us with what we need.
So, if we think about it: all of this starts in the ovary, but where it is felt the most is in the brain. Hot flashes, insomnia, brain fog and mood changes are, to a large extent, symptoms of the brain. For decades this stage was studied as a reproductive matter, and hardly anyone looked at the brain. Today, at last, it is being said out loud, and there are already studies that went and measured what happens in the brain instead of assuming it. That's why international guidelines don't suggest a specific specialty to treat you in this stage, but a health professional with experience in menopause, whatever her field.
When you understand this process, you understand the magnitude of this transition and you can look at your body with more compassion and patience in this stage, which some of us women have had to go through in a very hard way.
On this site you'll find somewhat more detailed information about this process, but always simple. Understanding it well will help you communicate better with the health professionals who can help you.
Have you already found a health professional who really knows about menopause? Recommend her on Instagram or by email (for now, only in Mexico). Your recommendation will help other women find her.
Still have questions about this topic? Write to us at [email protected].
Head too foggy to write? Don't worry, send us a voice note on Instagram.
Mention the code A5 · Menopause is being redefined so we know which piece you mean. I'll answer as soon as I can.
Sources
Brinton, R. D., Yao, J., Yin, F., Mack, W. J. and Cadenas, E. (2015). Perimenopause as a neurological transition state. Nature Reviews Endocrinology, 11(7), 393–405. https://doi.org/10.1038/nrendo.2015.82
Ellis, S., Franks, D. W., Nattrass, S., Cant, M. A., Bradley, D. L., Giles, D., Balcomb, K. C. and Croft, D. P. (2018). Postreproductive lifespans are rare in mammals. Ecology and Evolution, 8(5), 2482–2494. https://doi.org/10.1002/ece3.3856
Gravelsins, L. L., Perović, M., Wood Alexander, M., Splinter, T. F. L., McGovern, A. J., Rabin, J. S. and Galea, L. A. M. (2026). Reframing menopause and menopause hormone therapy as opportunities for healthy aging. Science, 394(6819), 60–68. https://doi.org/10.1126/science.aeg5004
Harlow, S. D., Gass, M., Hall, J. E., Lobo, R., Maki, P., Rebar, R. W., Sherman, S., Sluss, P. M. and de Villiers, T. J. (2012). Executive summary of the Stages of Reproductive Aging Workshop + 10: addressing the unfinished agenda of staging reproductive aging. Menopause, 19(4), 387–395. https://doi.org/10.1097/gme.0b013e31824d8f40
Lumsden, M. A. and Sassarini, J. (2019). The evolution of the human menopause. Climacteric, 22(2), 111–116. https://doi.org/10.1080/13697137.2018.1547701
Mosconi, L., Berti, V., Dyke, J., Schelbaum, E., Jett, S., Loughlin, L., Jang, G., Rahman, A., Hristov, H., Pahlajani, S., Andrews, R., Matthews, D., Etingin, O., Ganzer, C., de Leon, M., Isaacson, R. and Brinton, R. D. (2021). Menopause impacts human brain structure, connectivity, energy metabolism, and amyloid-beta deposition. Scientific Reports, 11, 10867. https://doi.org/10.1038/s41598-021-90084-y
National Institute for Health and Care Excellence. (2015, updated in 2026). Menopause: identification and management (NG23). https://www.nice.org.uk/guidance/ng23
Nattrass, S., Croft, D. P., Ellis, S., Cant, M. A., Weiss, M. N., Wright, B. M., Stredulinsky, E., Doniol-Valcroze, T., Ford, J. K. B., Balcomb, K. C. and Franks, D. W. (2019). Postreproductive killer whale grandmothers improve the survival of their grandoffspring. Proceedings of the National Academy of Sciences, 116(52), 26669–26673. https://doi.org/10.1073/pnas.1903844116
Secretaría de Salud [Mexican Ministry of Health]. (2013, January 7). Norma Oficial Mexicana NOM-035-SSA2-2012, para la prevención y control de enfermedades en la perimenopausia y postmenopausia de la mujer [Mexican Official Standard for the prevention and control of disease in women's perimenopause and postmenopause]. Diario Oficial de la Federación. https://dof.gob.mx/nota_detalle.php?codigo=5284235&fecha=07/01/2013
Where each fact comes from: perimenopause as a transition of the brain, not only a reproductive one: Brinton et al., 2015 (the source says “neurological”; here we say “neuroendocrine” because it includes the hormones), and Mosconi et al., 2021. Menopause as a single day, the day of the last period: STRAW+10 (Harlow et al., 2012) and NOM-035. More than a third of life after reproduction ends, and orcas: Lumsden and Sassarini, 2019. Post-reproductive stages are rare in mammals and limited to humans and a few species of toothed whales: Ellis et al., 2018. Orca grandmothers improve the survival of their grandchildren: Nattrass et al., 2019. Guidelines don't name a specialty but a health professional with experience in menopause: NICE NG23. That natural selection loses strength after reproductive age, and the mismatch with the modern environment, are hypotheses from evolutionary medicine; here they appear as the author's opinion.
I found the Science article thanks to Emilė Radytė, PhD (@dr.em.neuroscientist).
Who writes this
I'm Marcela Garza, founder of No exageras. I have been living with a perimenopause with very severe symptoms since I was 39. I'm not a doctor, researcher or journalist: I'm a patient, and the only purpose of this text is for us women to educate ourselves. No institution or company pays me to publish this, so there is no commercial agenda behind this content. For this piece I used artificial intelligence as a tool to search, review and organize the information and to polish some parts of the text. The questions, the decisions and the voice are mine. Every fact has its source, so you can check it yourself. If you find an error, write to us at [email protected] so we can correct it and enrich this information for other women.
What we share on No exageras are experiences and learnings from a patient's point of view; we do not give diagnoses or medical advice. Every body and every story is different: make any decision about your health with a health professional.