Improvement of sperm motility by the addition of progesterone to the Percoll medium during sperm purification.

The Percoll centrifugation technique is widely used to select the most motile spermatozoa in connection with assisted reproduction techniques (ART). Progesterone is known to enhance the motility of spermatozoa in vivo and in vitro. This study evaluates whether the motility of spermatozoa can be enhanced by the presence of progesterone simultaneously with purification using a routine Percoll centrifugation technique. Motility is measured by computer-assisted sperm analysis. The 100% Percoll medium contained a progesterone concentration of 2 micrograms/ml, which is in the range of that found in pre-ovulatory follicular fluid and peritoneal fluid around ovulation. With a two-layer purification procedure (55/80% Percoll medium), exposure of the progesterone in the Percoll medium for only 25 min caused a highly significant improvement of motility in the spermatozoa isolated from the semen samples of 14 healthy men. It is concluded that the addition of progesterone to the Percoll purification medium can further enhance sperm motility without the need for a change in the routinely used semen purification technique in most assisted reproduction programmes.