Reduction of steps in the preparation of motile sperm for intrauterine insemination does not reduce efficacy of the procedure: simplified one-step swim-up method versus classic swim-up

BACKGROUND: Intrauterine insemination (IUI) is a valid treatment for infertility with a cumulative pregnancy rate of >40-90% after 3-10 treatment cycles. We studied the efficacy of a simplified method for motile sperm preparation for IUI. METHODS: A prospective clinical trial was performed with 100 couples (male age 33-48 and female 28-37 years) with a 2-8 year history of primary infertility associated with slight oligozoospermia (16/100), oligomenorrhoea (32/100) or unknown (52/100). Motile sperm for IUI were prepared by: (A) the classic World Health Organization self-migration (swim-up) method which includes centrifugation, or (B) a simplified one-step swim-up procedure without centrifugation. Recombinant FSH was used for ovarian stimulation. Depending on the cause of infertility, patients were matched one-to-one at the time of IUI, so that when a total of 100 couples had been treated, 50/100 women received sperm prepared by method A and 50/100 by method B. RESULTS: A statistically significant correlation was found between the percentage motile sperm of the original semen sample and the percentage of motile sperm recovered by method A (r = 0.333, P < 0.01) and B (r = 0.400, P < 0.01). A highly significant correlation (r = 0.997, P < 0.001) was found between the two methods. CONCLUSIONS: The simplified one-step swim-up method was as effective as the classic swim-up method, but the former was easier and more economical.