BACKGROUND Previous research suggests the removal of uterine leiomyomata may improve ability to conceive. Most of this previous research was conducted in infertility clinics. We investigated the association between leiomyoma characteristics on time to pregnancy among women enrolled from the general population. METHODSWe enrolled a cohort study of women in early pregnancy. Participants retrospectively reported their time to conception. Leiomyomata characteristics were determined by first-trimester ultrasound. We used discrete time hazard models to estimate the effects of uterine leiomyomata on time to pregnancy. RESULTSIn this population of 3000 women, 11 (324) with one or more leiomyomata, we found no association between leiomyomata presence, type, location, segment or size on time to pregnancy. CONCLUSIONSThese results suggest that leiomyomata have little effect on time to pregnancy in this cohort of women. The study excluded women who had been treated for infertility, and this may have resulted in underestimation of the association. However, differences between our study and previous studies in specialty clinics may be, in part, attributable to differences between our community-recruited population of women and women receiving fertility care, as well as difference in leiomyomata size or type in women having myomectomies to treat infertility.