Hormonal contraception protects from asthma, study suggests

A study suggests that the use of hormonal contraceptives, used to suppress the activities of sex hormones and prevent pregnancy, could protect women from developing asthma

A study from researchers at the Asthma UK Centre for Applied Research suggests that the use of hormonal contraceptives, used to suppress the activities of sex hormones and prevent pregnancy, could protect women from developing asthma.

Asthma affects more than 300 million people in the world and more than five million people in the UK. It is more common in boys than in girls in childhood, but after puberty, can be more frequent and severe in women than in men. These sex differences have puzzled scientists for decades, but it is generally believed that female sex hormones may play a role.

Investigating the impact of hormonal contraception

Researchers from the University of Edinburgh and the Asthma UK Centre for Applied Research carried out a study which analysed data from over 600 GP practices across the UK. It involved more than 500,000 non-pregnant women aged 16-45 years, who were followed for 17 years.

The study indicates that women who used hormonal contraceptives, regardless of the type of contraceptives, were less likely to develop asthma than those who did not.

Additionally, women who used hormonal contraception for a longer period had greater protection than those who used the contraception for a shorter period.

A promising start for future research

Although this finding is promising for the prevention of asthma in women who develop the disease in adulthood, experts say that more research is needed to help understand the biological process through which hormonal contraceptives protect women from developing asthma.

Dr Bright Nwaru, Honorary Research Fellow at the Asthma UK Centre for Applied Research and lead author on the article said:

“Our study, which represents the largest undertaking so far on the role of hormonal contraceptives in the development of asthma in women, provides very promising results that now need to be taken forward to understand the biological processes through which hormonal contraceptives influence the development of asthma. Our findings also provide a window of opportunity to undertake clinical trials to investigate the safety and effectiveness of hormonal contraceptives for preventing the development of asthma in women."

Scientists say that women should continue to take medications as prescribed by their GP until further research provides clearer insights for these findings.

Read the article

Journal of Allergy and Clinical Immunology

Cite as

Bright I. Nwaru, Rebecca Pillinger, Holly Tibble, Syed A. Shah, Dermot Ryan, Hilary Critchley, David Price, Catherine M. Hawrylowicz, Colin R. Simpson, Ireneous N. Soyiri, Francis Appiagyei, Aziz Sheikh (2020), Hormonal contraceptives and onset of asthma in reproductive-age women: Population-based cohort study, Journal of Allergy and Clinical Immunology, 2020, ISSN 0091-6749, https://doi.org/10.1016/j.jaci.2020.02.027.