Objective: To evaluate the impact of uterine artery embolization (UAE) for fibroids on ovarian reserve in women younger than 40 years. Design: Prospective study. Setting: University-based reproductive endocrinology unit. Patient(s): Twenty regularly cycling women aged 33-39 years undergoing UAE for fibroids. All had cycle day 3 FSH levels <10 mlU/mL. Intervention (s): Measurements of serum FSH and E, levels and of the total ovarian volume and antral follicle number by transvaginal ultrasonography on day 3 of the menstrual cycle preceding UAE and on day 3 of the cycles occurring in months 3, 6, and 12 after UAE. Main Outcome Measure(s): Preprocedural and postprocedural hormone levels, ovarian volumes, and antral follicle numbers. Result(s): There were no significant changes from baseline in the mean day 3 FSH and E, levels, ovarian volume measurements, and antral follicle numbers measured at 3, 6, and 12 months after UAE. Conclusion(s): Although this study might be not sensitive enough to conclude that UAE for fibroids does not interfere with a woman's ovarian status, these data indicate that in this series of reproductive-aged women UAE did not have short- or mid-term effects on ovarian reserve as assessed by hormonal and sonographic parameters. (Fertil Steril(R) 2004;81:1055-61. (C) 2004 by American Society for Reproductive Medicine.).