Luteinized unruptured follicle syndrome: incidence and recurrence rate in infertile women with unexplained infertility undergoing intrauterine insemination.

BACKGROUND The objective of this study was to determine the incidence and recurrence rate of luteinized unruptured follicle (LUF) syndrome in women with unexplained infertility undergoing intrauterine insemination (IUI). METHODS A total of 167 women with unexplained infertility who underwent 292 cycles of IUI were enrolled in the study. All patients were treated with clomiphene citrate, 50-150 mg/daily from day 5 to 9 of their menstrual cycle. Ultrasound examination to confirm ovulation was performed on the day of IUI (day 0) and every day thereafter for another 3 days (days 1, 2 and 3). A total of 69 women who failed to conceive in the first cycle and 56 women who failed to conceive in the second cycle underwent second and third cycles, respectively. RESULTS Of the total 167 patients who underwent first cycle, 42 (25%) had LUF. The incidence of LUF was 56.5% in 69 patients who underwent a second cycle of IUI treatment, of whom 33 patients had LUF in the first cycle with recurrence rate of 78.6%. In 56 patients who underwent 3 consecutive cycles, the incidence of LUF was 58.9% and recurrence rate of 90%. No pregnancies were recorded in patients with LUF during the study period. CONCLUSION The incidence and recurrence rate of LUF are significantly increased in subsequent cycles of IUI. In these patients, other options of infertility treatment might be justified.