Influence of the swim-up procedure on acrosome damage induced by freezing human semen

Twenty frozen semen samples from normal donors were thawed, washed in Earle's medium, and allowed to swim up using standard techniques. The samples were evaluated before and after the swim up for progressive motility and concentration. Morphologically normal sperm were assessed for acrosomal integrity according to the relative percentages of normal, damaged or lost acrosomes. The motility improved by 75.07 +/- 90.38%, the count was reduced by 97.1 +/- 1.9%, but there was no significant change in the frequencies of the different types of acrosome state. It was concluded that although the swim-up technique is successful in reducing most major morphological abnormalities, influence over the frequencies of secondary acrosomal abnormalities could not be demonstrated.