Silva, Selma Bruno daViana, Elizabel de Sousa RamalhoSousa, Maria Bernardete Cordeiro de2010-08-302010-08-302006SILVA, S. B.da ; VIANA, E de S. R. ; SOUSA, M. B. C. de . Changes in peak expiratory flow and respiratory strength during the menstrual cycle. Respiratory Physiology and Neurobiology , Estados Unidos, v. 150, n. 2-3, p. 211-219, 2006https://repositorio.ufrn.br/jspui/handle/1/2932This study evaluated the spirometry and respiratory static pressures in 17 young women, twice a week for three successive ovulatory menstrual cycles to determine if such variables changed across the menstrual, follicular, periovulatory, early-tomid luteal and late luteal phases. The factors phases of menstrual cycle and individual cycles had no significant effect on the spirometry variables except for peak expiratory flow (PEF) and respiratory static pressures. Significant weak positive correlations were found between the progesterone:estradiol ratio and PEF and between estrogen and tidal volume (r = 0.37), inspiratory time (r = 0.22), expiratory time (r = 0.19), maximal inspiratory pressure (r = 0.25) and maximal expiratory pressure (r = 0.20) and for progesterone and maximal inspiratory pressure (r = 0.32) during the early-to-mid luteal phase. Although most parameters of the spirometry results did not change during the menstrual cycle, the correlations observed between sexual hormones and respiratory control variables suggest a positive influence of sexual female hormones controlling the thoracic pump muscles in the luteal phaseporAcesso AbertoBreathing controlRespiratory pressureFemale hormonesSex steroidsControle da respiraçãoHormônios femininosEsteróides sexuaisarticle