[Spermatic fertilization capacity after swim-up spermatozoa recovery technique].

Objectives: To investigate sperm quality before and after swim up in infertile patients, and to compare it with a fertile men population.

Methods: Semen samples from 55 patients consulting at the infertility services of the Hospitals "Centenario" in Rosario and "Eva Perón" in Gro Baigorria were collected and analyzed accordingly with the WHO guidelines. 30 sperm samples with a volume higher than 1.0 ml, and spermatozoid concentration higher than 5,000,000/ml, not presenting hyperviscosity were selected. Outcome variables including progressive mobility (PM), morphology (M), chromatin condensation (CC) and chromatin integrity (CIl, were compared in fresh semen samples, between patients without previous treatment (G2) and after swim up (G3) and 15 fertile men (G1). Sperm morphology was evaluated by brilliant green hematoxyllin stain; progressive mobility with a subjective method accordingly to WHO (1999); chromatin condensation with aniline blue test; and chromatin integrity with acridine orange as fluorocrom. Swim up technique was based on Berger et al. ( 1985) with mHTF, heatingthe samples in a Falcon tube in a 45 degree angle in a 37 degree C gas heater for one hour (5% CO2 atmosphere). Following incubation 0.5 ml of the overlay containing sperm cells that swam up from the pellet were removed to process the recovered spermatozoids. Student's t test was applied to compare PM, M, CC, and CI between the four groups. A significant difference was found between G1 vs G3 and G2 vs G3 (p < 0.001). No significant differences were found between G1 and G3 (p > 0.1). It showed that PM, M, CC and C1 parameters in the recovered spermatozoids after swim up were similar to fertile population.

Conclusions: Our results indicate that through the swim up procedure gametes with fertile ability similar to normal fertile population can be recovered to be applied in low complexity in vitro fertilization techniques such as intrauterine insemination, where the natural selection is still viable.