Comparison of four methods for sperm preparation for IUI.

We compared the pregnancy rates and sperm characteristics of semen prepared by the albumin, Percoll, Puresperm, and swim-up methods. Semen analysis was performed by a computer-assisted system (CASA). The overall pregnancy rate was 14% per patient and 11% per cycle. The albumin and Percoll methods had the highest pregnancy rates, up to 12% per cycle. We then compared each method with the albumin method. The swim-up technique yielded the highest percentage of motile sperm. The Percoll method yielded statistically significant changes in average path velocity and straight-line velocity, while the Puresperm method revealed the same statistical changes in total concentration and hyperactive motile sperm percentage. After adjusting for age, methods, and CASA estimates, only straight-line velocity was significantly correlated with pregnancy. Although the Percoll method was associated with the best pregnancy rate, this product has been withdrawn from the market because of toxic contamination. Puresperm had replaced it in our laboratory but showed an unsatisfactory pregnancy rate. The swim-up method is the best choice for IUI.