RESUMEN
This study was done in the Department of Obstetrics and Gynecology, Menoufiya University Hospital. It included 57 couples with unexplained infertility. They were normal regarding semen analysis, ovulation and tubal patency, with no mechanical barrier to oocyte capture. Controlled ovarian stimulation was done using clomiphene citrate combined with human menopausal gonadotropin. Intrauterine insemination was performed at 36 hours after triggering ovulation by hCG injection. Transvaginal ultrasonography with 5 MHz pulsed Doppler system was used for the assessment of follicular development and uterine and ovarian blood flow velocity waveforms in different phases of the menstrual cycle. The study concluded that blood flow studies of uterine and ovarian vessels, measurement of endometrial thickness and pattern and the number of mature ovarian follicles before ovulation constitute good predictors for successful implantation