RESUMEN
The hypo-osmotic swelling test is useful in the evaluation of the sperm membrane's integrity, The association between a standard hypo-osmotic swelling test [HOS], and a simplified water HOS, and the pregnancy outcome was investigated, in sixty men and their wives who had patent tubes and evidence of ovulation with at least 12 months infertility. Data analysis showed that the men had a mean age of 34.8 +/- 6.1 [range 21-65] years, mean fertility duration of 7.4 +/- 3.9 [range 2 - 21] years; 86,7% had primary infertility. There was a strong correlation between standard HOS and water HOS tests [r = .71, P<.01] and between the total spermatozoal motility and the HOS tests [r = 0.63 and r = 0,59, P<.01]. Water HOS with > 60% resulted in a 38.5% pregnancy rate, compared to an 8.3% pregnancy rate in those with water HOS 50-59% [P <.001] and 2.9% for HOS below 50%. Water HOS has a strong correlation with a standard HOS and can therefore be used in place of the latter