Perifollicular blood flow and pregnancy in superovulated intrauterine insemination (IUI) cycles: an observational comparison of recombinant follicle-stimulating hormone (FSH) and urinary gonadotropins.

The group of patients who received urinary gonadotropins (n = 117) for follicular stimulation had a significantly higher incidence of high perifollicular blood flow compared with that of the group who received recombinant FSH (n = 114; 46.3% vs. 22.7%). The overall clinical pregnancy rate in patients stimulated with recombinant FSH was 10.91%, compared with 22.22% in the group stimulated with urinary gonadotropins.