Background: Sperm preparation and acrosomic reaction have been largely studied to explain the physiology of sperm as reproductive cell.
Objective: To identify the morphological changes on in vitro prepared human sperm cells and in spontaneous and ionophore A23187 induced acrosome reaction of infertile males, through the application of the chlortetracycline test.
Design: Experimental prospective study.
Materials and methods: Sperm samples of 17 subfertile males were processed as routine for a sperm analysis, we carried out sperm preparation and induction of the acrosomic reaction by means of calcium ions A23187. The prepared sperm with direct swim-up was assessed at one hour and at four hours. Direct aliquots were taken and processed for the test with CTC, we considered as positive result obtaining more than 15% increase in the induced AR versus spontaneous.
Results: The whole population was classified as asthenozoospermic. Eight training morphological patterns were identified and we found four types of responses for the induced AR: Type I had an increase at one and at four hours incubation (47%); type II had an increase only after 1 hour incubation (23.5%); type III had an increase only at 4 hours incubation (17.7%), and type IV did not have increase (11.8%).
Conclusion: These results suggest that in astenozoospermic patients the training process has variations during the incubation time, demonstrated by the response at A23187. These findings could let us to select better spermatozoa in this group of males at the moment when capacitance is actually attained, thus being able to carry out more effective techniques in assisted reproduction.