SFRP4 and leiomyoma: Examining our additional 26 matched specimens of myometrium and leiomyoma, we found that levels of sFRP4 transcript were 4.2 times higher in leiomyomas collected during the proliferative phase of the menstrual cycle (n = 10, P < 0.001) but only 2.9 times higher in specimens of luteal phase leiomyomas (n = 9, P < 0.01) [Fig. 3(a)].