Hormonal Birth Control & Chronic Sinusitis: New Study Findings

A new study published in the February 2026 issue of Otolaryngology–Head and Neck Surgery suggests a potential link between estrogen-containing hormonal contraceptives and a reduced risk of chronic rhinosinusitis without nasal polyps (CRSsNP) in women. The research, analyzing data from nearly 240,000 women participating in the National Institutes of Health’s All of Us Research Program, adds to a growing body of evidence exploring the influence of sex hormones on inflammatory conditions.

Chronic rhinosinusitis, an inflammation of the sinuses, affects millions of people, causing symptoms like nasal congestion, facial pain, and loss of smell. CRSsNP, specifically, refers to the condition without the presence of nasal polyps – growths in the lining of the nasal passages. While the exact causes of chronic rhinosinusitis are complex and not fully understood, inflammation plays a central role.

“We know that inflammation differs between the biological sexes and that sex hormones play a role in inflammation – a relationship has been well established in asthma and other inflammatory diseases,” explained Dr. Victoria S. Lee, Associate Professor and Director of Research with the Department of Otolaryngology at the University of Illinois College of Medicine, and senior author of the study. “Relatively little research, however, has examined the role of biological sex and sex hormones in CRS, another inflammatory airway disease.”

The study’s findings indicate that women using estrogen-containing hormonal contraceptives (ECCs) had a lower odds of developing CRSsNP compared to women who did not use hormonal contraception. Specifically, the odds ratio was 0.71, with a 95% confidence interval of 0.64-0.80. This suggests a statistically significant association, meaning the observed reduction in risk is unlikely due to chance.

Interestingly, the research did not find a similar association between progestin-only contraceptives (POCs) and CRSsNP. Menopause status, representing a state of estrogen depletion, showed no significant association with the condition. Participants who had gone through menopause had an odds ratio of 1.02 compared to premenopausal patients, with a 95% confidence interval of 0.94-1.11.

Beyond the association with CRSsNP risk, the study also explored biomarker data. Researchers found that ECC use was associated with a decreased serum neutrophil concentration – a type of white blood cell involved in inflammation – both in participants without CRS and in those with CRSsNP. This suggests a potential mechanism by which estrogen-containing contraceptives might exert their protective effect, by modulating the inflammatory response.

The research team had previously observed that CRSsNP more commonly affects women than men during their reproductive years, prompting this deeper investigation into the role of sex hormones. “To address this knowledge gap, our research team previously showed that CRSsNP more commonly affects women than men during the reproductive years,” Dr. Lee stated. “Building on this work, the present study extends these findings by looking at the influence of sex hormone-based contraceptives and menopause, an estrogen-deprived state.”

The study utilized a cross-sectional analysis of data from 239,564 participants in the All of Us Research Program, a large, national dataset aiming to gather health information from a diverse population. This large sample size strengthens the reliability of the findings. However, it’s important to note that the study design – a cross-sectional analysis – cannot establish cause and effect. It can only demonstrate an association between ECC use and lower CRSsNP risk.

Researchers emphasize the need for further investigation to clarify the underlying mechanisms driving this association. The study authors suggest that understanding these mechanisms could lead to improved risk stratification and potentially inform hormone-related therapy recommendations for women with CRS. “this work has the potential to improve risk stratification and inform hormone-related therapy recommendations for women with CRS,” Dr. Lee said.

While the findings are promising, it’s crucial to avoid drawing definitive conclusions about treatment or prevention strategies at this stage. The study does not recommend that women start or stop using hormonal contraceptives based on these results. Instead, it highlights an area for continued research and a potential avenue for developing more targeted therapies for chronic rhinosinusitis in women.

The study also acknowledged that further research is needed to understand the impact of hormonal changes on nasal conditions, particularly in the long term. This is especially relevant considering the potential for chronic issues to develop after significant hormonal shifts, such as those experienced during pregnancy, as noted in related research exploring the impact of pregnancy-associated hormonal changes on sinusitis.