Pelvic floor muscle exercises are one of the main conservative options for the treatment of female urinary incontinence. Despite this widespread use, there is very little information on 'normal' pelvic floor function. In a prospective observational study the authors intended to define the spectrum of normality for pelvic floor function in women, assessing 206 nulliparous women recruited early in their first ongoing pregnancy. Levator function was evaluated using translabial ultrasound: cranioventral displacement of the bladder neck was utilized to quantify levator activity. The presence of a reflex contraction of the external perineal muscles and levator on coughing was registered, as was the strongest of at least three contractions. Only 41 of 206 women (20%) had ever been taught pelvic floor exercises by a health professional, and this had been exclusively verbal. Teaching had no influence on levator strength. Spontaneous contractions on request were obtained in 172 women (85%). Advice was necessary in 96 women (47%) in order to obtain an optimal contraction. Reflex muscle activation on coughing was documented in 118 women (57%) and was associated with a stronger contraction (P<0.001). Reported use of the levator muscle on intercourse was strongly associated with increased levator activity (P<0.001). Motivational factors mentioned were boyfriends, mothers, other female relatives and, most commonly, articles in popular magazines, e.g. Cosmospolitan and Cleo.