A study carried out at the University of São Paulo (USP) highlighted the influence of female sex hormones on pain sensitivity . Conducted in the Graduate Program in Systems Biology at the Institute of Biomedical Sciences (ICB), the research investigates how the estrous cycle — a set of physiological changes that occur in female mammals and are caused by reproductive hormones — affects pain perception in Wistar rats, revealing significant variations throughout the hormonal phases.
The work was led by Natasha Farias Marques under the guidance of professor Marucia Chacur and showed that sensitivity to pain increases during diestrus, a phase of the cycle characterized by low hormonal levels.
“Progesterone replacement in rats with their ovaries removed demonstrated a protective effect against pain, while estradiol has not shown a significant impact so far,” explains Marques, in a statement.
The study, in addition to showing the impacts of female sex hormones on general health, highlights the need to include more females in scientific studies.
“Most studies use only males, because their results are not influenced by hormonal variations. However, this limits the understanding of biological differences and impedes advances in personalized treatments”, warns Chacur.
How was the work done?
To reach its conclusions, the study used ethical and rigorous methods to assess pain sensitivity at different phases of the estrous cycle. These include pressure tests on the paw, tactile stimuli and collection of vaginal lavage to monitor the phases of the cycle — a non-invasive procedure similar to the Pap smear.
Furthermore, some of the rats used in the study underwent ovariectomy, simulating a menopausal condition, which made it possible to analyze the impact of hormone replacement.
“The data shows that progesterone reduces pain sensitivity, suggesting its potential as a basis for future therapies. Work like this is crucial for the advancement of science and the development of more effective and individualized treatments”, says Chacur.
The study was recognized with an honorable mention at the Congress of the Brazilian Society of Neurosciences and Behavior (SBNeC). In April 2025, the results will be presented at the 14th Congress of the European Pain Federation (EFIC), in Lyon, France, expanding the dialogue on the importance of studies that consider biological differences between the sexes.
Research shows that 82% of menopausal women report depression
This content was originally published in Female hormones can impact pain sensitivity, says study on the CNN Brasil website.
Source: CNN Brasil
I am an experienced journalist and writer with a career in the news industry. My focus is on covering Top News stories for World Stock Market, where I provide comprehensive analysis and commentary on markets around the world. I have expertise in writing both long-form articles and shorter pieces that deliver timely, relevant updates to readers.
