P-25: Semen attributes and sperm hyaluronic acid binding after 2-3 days and 1 day abstinences in 418 normozoospermic and oligozoospermic men

Abstract

We have evaluated the effects of abstinence period on motile sperm concentrations and sperm fertilizing potential in husbands of couples treated with intrauterine insemination. Comparison of semen attributes and sperm biochemical markers of maturity and zona pellucida binding ability, in first day (2-3 days abstinence) and second day (1 day abstinence) semen samples of husbands of couples treated with IUI. Sperm concentration and motility were evaluated by CASA (Hamilton-Thorne). Sperm maturity was assessed by HspA2 chaperone measurements (reflects proportion of mature sperm) and sperm creatine kinase (CK) activity (reflects cytoplasmic retention in immature sperm). Sperm fertilizing potential was measured by hyaluronic acid (HA) binding (proportion of sperm able to bind to the zona pellucida of oocytes) using the HBA slide assay (MidAtlantic Diagnostics). Statistical evaluations by paired T-test and Wilcoxon ranked sum test were performed by the Sigma Stat program (Jandel Scientific Co). All values are expressed as mean±SEM. The mean sperm concentrations in the 1D vs. 2-3D groups were 51.8±1.8x106 vs. 62.9±2.4 X 106 sperm/mL (N=418 men, P<0.001). The decline in sperm concentrations after 1D vs. longer abstinence periods has been well established. However, detailed analysis of the large group of 418 men revealed previously unobserved improvements in oligozoospermic and asthenozoospermic men. The 2-3D vs. 1D sperm concentrations in men of the <20x106 sperm/mL semen oligozoospermic range (N=84 men) were: 12.4±0.61 vs. 18.6±2.1 (p=0.03). However, in men in the >20x 106 sperm/mL normozoospermic range, there was a decline in 2-3D vs. 1D abstinence groups: 75.27±2.6 vs. 59.93±2.63; (P<0.001). The mean sperm motilities in the 2-3D and 1D groups (N=221) were unchanged: 53.3±1.1% vs. 55.7±1%. However, similar to the sperm concentration data, the asthenozoospermic men revealed an improvement in sperm motility after 1D abstinence. In the <40% motility range (N=45), the 2-3D vs. 1D motilities were 30.7±2.2% vs. 39.7±2.2% (P<0.001). However, in the >40% motility range, (N=176) the motilities were similar: 61.6±0.8% vs. 59.9±2.9. The mean values for CK activity, a marker of diminished sperm maturity and surplus cytoplasm, in the 2-3 D vs. 1 D groups were 0.31±0.05 vs. 0.43±0.04 CK IU/108 sperm (P<0.001, N=402), indicating a lower proportion of immature sperm after 2-3D abstinence. Similarly, the other sperm maturity marker, HspA2 ratio, showed a mean overall decline from the 2-3D to the 1D samples from 39.4% to 27.9% (P<0.006, N=405). With respect to sperm-hyaluronic acid binding, which reflects the proportion of sperm able to bind to the zona pellucida, there was only a slight decline in the 2-3D vs. 1D groups from 89.7±0.8 to 87.4± 0.9% (P< 0.01, N=181). In general, there is an abstinence-related decline in sperm concentrations and motility. However, analysis of the present large population of 415 men suggests that in oligozoospermic and asthenozoospermic men there are improvements in sperm concentration and motility, respectively, with short term abstinence. These data, along with those for the sperm maturity attributes, indicate that abstinence-related variations do not substantially affect the efficacy of IUI treatment in oligozoospermic and asthenozoospermic men, who benefit most from this therapeutic modality.