Aurélie Carlier uses mathematics to improve healthcare for women

Why do we still know so little about the differences between men and women? “Until the 1990s, clinical trials were not required to test medicines on both sexes", Carlier explains.

Because of the menstrual cycle, women were traditionally seen as more variable and therefore more complex research subjects. As a result, researchers tended to test medicines primarily on men. Carlies explains: “The problem was that researchers assumed men and women would respond in the same way.”

Although medicines are now routinely tested on both men and women, Carlier believes there is still considerable room for improvement. “Sex differences are only taken into account relatively late in the process”, she says. “Clinical research starts at cellular level and is then gradually expanded to include male and female participants. In my research, I try to incorporate those differences from the very beginning, because even cells are inherently male or female.”

Because sex differences are often only considered at a later stage, some side effects are discovered too late. In some cases, researchers are forced to halt a study shortly before completion, after significant amounts of time and funding have already been invested. “Sometimes certain effects only become apparent once a medication has reached the market", Carlier adds. “I want to help prevent that, for example by adjusting dosages for women and men from the outset, reducing the risk of adverse reactions.”

In addition to dosage, Carlier’s research could also improve the timing of treatments. This is particularly relevant for cancer therapies, where the menstrual cycle may play an important role. “At the moment, we do not take hormones into account,” she says. “Yet the point in a woman’s cycle at which she receives chemotherapy, for example, may affect how effective the treatment is. Much more research is needed in this area.”
 

Carlier’s work could fundamentally change the way medical research is conducted in the future. The need for animal testing and human trial participants may gradually decrease. “I am developing what are known as ‘digital twins’", she explains. “They are essentially digital versions of real people. The idea is that, eventually, they will be able to predict with great accuracy what would happen in real life.”

This could make it easier to conduct research involving groups such as children and pregnant women. But the potential applications go even further. “Imagine you need heart surgery", Carlier says. “A surgeon could first use a virtual model of your heart to calculate which treatment would work best for you. For example, which heart valve would be most suitable or which medication best fits your situation. But that is still very much something for the future.”

Alongside her research, Carlier is committed to advancing equality in academia. She founded the Female Empowerment Maastricht (FEM) network and, in 2022, organised the first ‘Women in Biomechanics’ session at the European Society of Biomechanics conference. It has since become a recurring part of the conference programme.

For these efforts, she received the NWO Athena Award last year, a prize recognising outstanding female researchers who also serve as role models for others. According to Carlier, such role models are still urgently needed. “In my field, you still often work in a male-dominated environment", she says. “At conferences, people have asked me where the coffee was because they assumed I was the secretary.”

After having children, she became even more aware of the additional barriers women face. “I was breastfeeding and had to express milk in a broom cupboard at work because there was no lactation room nearby. These may seem like small things, but they shape whether you feel you truly belong in academia.”

That is why she is particularly committed to supporting young female researchers. “I see many talented women leave academia because they do not want to spend their entire careers fighting all those obstacles. I think that is incredibly unfortunate, especially when an academic career is exactly what they would have wanted.”