The prevalence of BHR was 13% (fall of or greater than 20% in FEV(1) up to a maximal cumulative dose of 2 mg), and 6% had asthma.
There was an increase in BHR within the window of risk (odds ratio [OR], 2.3). The OR lower than 1 in women using oral contraceptives (OCs).
There is variation in BHR during the menstruation cycle, supporting the hypothesis of a hormonal influence. Oral contraceptives (OCs) appear to have a protective effect.
Perimenstrual increase in bronchial hyperreactivity in premenopausal women: Results from the population-based SAPALDIA 2 cohort. Dratva J, Schindler C, Curjuric I, Stolz D, Macsali F, Gomez FR, Zemp E; on the behalf of the SAPALDIA Team. J Allergy Clin Immunol. 2010 Mar 12.
Women are more likely to be diagnosed with asthma and suffer greater morbidity than men. Medscape, 2011.
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