Association of uterine fibroids and pregnancy outcomes after ovarian stimulation-intrauterine insemination for unexplained infertility.

OBJECTIVE: To investigate the association of non-cavity-distorting uterine fibroids and pregnancy outcomes after ovarian stimulation-intrauterine insemination (OS-IUI) in couples with unexplained infertility.

DESIGN: Secondary analysis from a prospective, randomized, multicenter clinical trial investigating fertility outcomes after OS-IUI.

SETTING: Reproductive Medicine Network clinical sites.

PATIENT(S): Nine hundred couples with unexplained infertility who participated in the Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation (AMIGOS) clinical trial.

INTERVENTION(S): Participants were randomized to one of three arms (clomiphene citrate, letrozole, or gonadotropins), and treatment was continued for up to four cycles or until pregnancy was achieved.

MAIN OUTCOMES MEASURE(S): Conception (serum hCG increase), clinical pregnancy (fetal cardiac activity), and live birth rates.

RESULT(S): A total of 102/900 participants (11.3%) had at least one documented fibroid and a normal uterine cavity. Women with fibroids were older, more likely to be African American, had a greater uterine volume, lower serum antimüllerian hormone levels, and fewer antral follicles than women without fibroids. In conception cycles, clinical pregnancy rates were significantly lower in participants with fibroids than in those without uterine fibroids. Pregnancy loss before 12 weeks was more likely in African American women with fibroids compared with non-African American women with fibroids. There was no difference in conception and live birth rates in subjects with and without fibroids.

CONCLUSION(S): No differences were observed in conception and live birth rates in women with non-cavity-distorting fibroids and those without fibroids. These findings provide reassurance that pregnancy success is not impacted in couples with non-cavity-distorting fibroids undergoing OS-IUI for unexplained infertility.

CLINICAL TRIAL REGISTRATION NUMBER: NCT01044862.