The study of asthma in fertile women needs to consider its potentially recurrent exacerbation in a specific phase of the menstrual cycle.Premenstrual asthma(PMA)refers to the deterioration of asthma in some women of fertile age during the premenstrual phase.Prevalence varies considerably according to studies(11%-47.44%)mainly because there is no standardized definition of the illness.There is a possible link between PMA and premenstrual syndrome,which is a set of physical and psychic manifestations that occur in some fertile women during the same premenstrual phase.This relation has been widely studied but there are still several unknowns.PMA etiopathogeny is not known.It involves possible causes such as hormonal variations in the premenstrual phase,the coexistence of atopy,variations during the cycle in substances related to inflammation,like LTC4 leukotrienes,catecholamines,E2 and F2αprostaglandins and certain cytokines.Also considered are psychological factors related to this phase of the menstrual cycle,a high susceptibility to infection or increased bronchial hyperreactivity prior to menstruation.Yet no factor fully explains its etiology,consequently no specific treatment exists.Researchers have investigated hormones,antileukotrienes,prostaglandin synthesis inhibitors,diuretics,phytoestrogens and alternative therapies,but none has been shown to be effective.