Hormones in menstrual cycle may worsen asthma symptoms, study finds

An asthma inhaler.

Norwegian researchers have found a woman’s menstrual cycle may affect the severity of respiratory illnesses such as asthma.

After studying nearly 4,000 women, the research team led by Haukeland University Hospital in Bergen found that symptoms such as breathlessness and wheezing worsened around the time of ovulation, the BBC reported.

The findings were published in the American Journal of Respiratory and Critical Care Medicine.

RedOrbit.com reported that none of the women who participated in the study were taking hormonal contraceptives and all had regular menstrual cycles lasting 28 days or less.

Nearly 30 percent of the women were smokers and eight percent were asthma sufferers.

“We found that respiratory symptoms varied significantly during the menstrual cycle,” the researchers said, according to red.Orbit.com.

“There were large changes in symptom incidence through the cycle for all symptoms. These relationships indicate a link between respiratory symptoms and hormonal changes through the menstrual cycle.”

According to the BBC, the charity Asthma UK said the findings could help women with asthma manage their illness more effectively.

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