Around nine million women in Germany are currently menopausal – and a third of them suffer from unpredictable hot flashes. How can we help them? Hormone expert Nina Rogenhofer explores this question at LMU University Hospital’s Grosshadern Campus.
To talk to Nina Rogenhofer, you have to follow the orange dots. Bright spots on pale gray, they mark the way to the LMU Hormone and Fertility Center, guiding patients along the seemingly endless corridor of the hospital building in Grosshadern. “Keep going straight ahead for another little while and then it’s the last door on the right before the bend,” says a helpful young orderly. “Warm, warmer, hot,” he calls out until the right door finally comes into view – without realizing just how fitting his words are.
After all, our discussion will be about heat. A particular form of heat that seems to come from nowhere: without any warning, without recognizable triggers, and with brutal force. About heat that pushes dark flushes into the face, makes the heart race, and drives sweat out of pores for minutes, soaking hair and clothing. Everything sticks, and nothing helps. “And now imagine you’re in a meeting when this happens,” says Professor Nina Rogenhofer, acting director of the Hormone and Fertility Center at LMU’s Grosshadern Campus.
Her patients often find themselves in such unpleasant situations: During the (peri-)menopause, which might begin at the age of 40 (sometimes even earlier) and in average at 53 or more, roughly a third of women suffer from hot flashes. Hormones do not respect important meetings or professional obligations, and do not understand embarrassment or tact. “And during the menopause, hormones can go pretty crazy,” says Rogenhofer.
Nina Rogenhofer at LMU Klinikum Großhadern
© Manu Theobald / LMUNina Rogenhofer
Vasomotor symptoms, better known as hot flashes, are a common feature of the menopause, the period in which the female body loses its fertility and phases down production of the sex hormones estrogen and progesterone. This hormonal adjustment can take up to ten years and begins before a woman’s final menstruation. “In the perimenopause, hormone levels strongly fluctuate, the cycle becomes irregular, and typical menopause symptoms can arise,” explains Rogenhofer. One year after a woman’s last period, we speak of the postmenopause – women are on average 52 years old when they reach this stage. “Hormonal fluctuations are in the foreground during the perimenopause, until the period finally stops altogether. But menopause symptoms can last for a while longer. If a woman then has a lack of estrogen, the risk of osteoporosis and cardiovascular diseases increases.”
Typical symptoms such as hot flashes, difficulty sleeping and concentrating, mood swings, headaches, and bone pain are thus fostered first by strong hormonal fluctuations and later by hormonal deficiency. Yet this does not apply to all women, as Rogenhofer emphasizes: It is thought that one third of women come through the menopause largely without symptoms, a third are not impaired in their everyday lives, and a third suffer a lot. Genes, body weight, and lifestyle influence how a person comes through the menopause – but nobody knows as of yet why exactly some women hardly feel a thing while others go through hell.
© Susan Wilkinson / unsplash
This presents medicine with a conundrum: There is a large group of people suffering from severe symptoms, but with no disease – after all, hormonal changes are a natural part of aging. This could be one reason why researchers devoted such scant attention to the topic for so long. On top of this, there is gender bias, the proven tendency in medicine to take women’s suffering less seriously and dismiss it as psychological. This makes it all the more important to give women effective guidance and support through the menopause – even though this is often a major challenge in view of the variety and duration of symptoms. “Hormones are an extremely complex subject and require a lot of professional knowledge, for sure, but also sensitivity, time, and sometimes almost the instincts of a detective.”
Studies and drugs require nuanced consideration, observes Rogenhofer, noting that large gaps in our knowledge still exist. A key factor in hot flashes was discovered only recently. “Estrogen plays an important role in the thermoregulation of the body, because it keeps neurotransmitters responsible for thermoregulation in equilibrium,” explains Rogenhofer. There is a particular focus here on so-called KNDy (pronounced “candy”) neurons. These are nerve cells that release neurotransmitters like kisspeptin, neurokinin B, and dynorphin A. If estrogen levels fall, the equilibrium of these neurotransmitters can get out of kilter, which then puts the KNDy neurons on high alert. They become overactive and can trigger hot flashes.
Nina Rogenhofer
The example illustrates how important research is in this field. Since we discovered how hot flashes originate, effective drugs have been developed to treat them. Fezolinetant, for example, blocks receptors for the neurotransmitter neurokinin B – and is thus effective at soothing hot flashes and night sweats. The drug was approved for use in Germany at the start of 2024. “The more we understand, the better we can treat menopause symptoms,” says Rogenhofer, “but there’s still room for improvement.”
Nina Rogenhofer at her office
© Manu Theobald / LMURogenhofer is encouraged by all the activity in this area over the past few years. After the breaking of many taboos around the cycle, the menopause seems to be attracting more attention. Not least because studies have shown that the menopause not only has health consequences, but an economic dimension. Data from the United Kingdom, for example, shows that around 42 percent of women are thinking about reducing their working hours or quitting their profession due to menopause symptoms.
Despite gaps in research and the need to make up for lost time, medicine is not entirely powerless against hormonal symptoms during the menopause. Hormone replacement therapy (HRT), for instance, is an effective way to alleviate them. However, it is not suitable for all women – nor is it wanted by all women, as it can increase the risk of breast cancer, if only marginally. Rogenhofer thinks that administering bioidentical hormones can be a useful tool, because the advantages outweigh the disadvantages for most women. HRT can also protect against osteoporosis, diabetes, and cardiovascular diseases. “All the same, it’d be nice if there wasn’t just one effective treatment,” she laments.
© Susan Wilkinson / unsplash
Aside from taking hormones and new drugs against hot flashes, there is not much else. Plenty of exercise, a healthy diet, and a normal weight are very important for women going through the menopause. And sometimes taking phytoestrogens can help. These are plant compounds that resemble the hormone estrogen in their chemical structure. Accordingly, they occupy the same receptors and can have a regulating effect on hormonal balance.
However, their effects have not been demonstrated clearly enough and can be insufficient when dealing with strong symptoms. By contrast, there is a solid body of evidence for bioidentical hormones. Generally, Rogenhofer calls on people not to demonize hormone replacement therapies. “In the case of thyroid deficiency, everybody is happy that bioidentical hormones exist. But as soon as it’s about sex hormones, a lot of anxieties come into play.”
The doctor could talk about hormones until the cows come home, but her time is precious. In the waiting room, there are two couples who want to discuss their plans to start a family. There’s just about time for one final question: Does she have a favorite hormone? Rogenhofer nods: “Happy hormones like dopamine, serotonin, and endorphins. I find it utterly fascinating how they influence our mood. Even a smile can boost their production,” says Rogenhofer – with a broad smile.
Prof. Dr. med. Nina Rogenhofer is gynecologist and hormone expert. She is acting director of the Hormone and Fertility Center at LMU University Hospital’s Grosshadern Campus.
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