THE RELATIONSHIP BETWEEN MORPHOLOGY, MOTILITY AND ZONA-PELLUCIDA BINDING POTENTIAL OF HUMAN SPERMATOZOA

Prediction of the fertilizing potential of human gametes under in vitr o conditions has been a major field of interest of assisted reproducti ve programmes. However, sperm morphology has been regarded as a predic tor of human in vitro fertilization rate. This paper prospectively eva luates the relationships among normal sperm morphology and (1) motion characteristics viz. curvilinear velocity (VCL), straight line velocit y (VSL), and linearity (LIN) (n = 37) and (2) spermzona pellucida bind ing capacity under HZA conditions (n = 144) of two separate groups of infertile couples. Semen was evaluated for sperm concentration, percen tage motility, forward progression, and percentage normal morphology ( strict criteria). The motility characteristics were measured using a c omputerized Sperm Motility Quantifier (SMQ). The zona binding potentia l of sperm was evaluated using the hemizona assay. Firstly, the VCL si gnificantly differred between the P-pattern and both the G (72.9+/-7 v s. 86.3+/-16 mu m P = 0.04) and N patterns (72.9+/-7 vs. 91.0+/-15 mu m s(-1); P = 0.002). The VSL differed only between the P and N pattern s, being 19.7+/-7 vs. 32.6+/-15 mu m s(-1) (P = 0.02), respectively. N o significant differences in LIN were noted between any of the three p atterns. The sperm concentration differed significantly between the P and both the G (37.9+/-35 vs. 80.8+/-9 x 10(6) ml(-1); P = 0.03) and t he N patterns (37.9+/-35 vs. 89.7+/-72 x 10(6) ml(-1); P = 0.05). Sign ificant differences were observed in the percentage motility between t he P and both the G (38.0+/-21% vs. 43.7+/-9%; P = 0.03) and the N pat terns (38.0+/-21% vs. 52.1+/-8%; P = 0.04). In the second study, the h emizona indices (HZI) differed significantly between the P and both th e G (29.3+/-26% vs. 57.6+/-62%; P = 0.01) and the N patterns (29.3+/-2 6% vs. 102.4+/-80%; P < 0.001). The G and N patterns also differed sig nificantly in their HZI (57.6+/-62% vs. 102.4+/-80%; P = 0.005). Sperm concentration differed between the P and both the G (32.8+/-29 vs. 76 .1+/-54 x 10(6) ml(-1); P < 0.001) and the N patterns (32.8+/-29 vs. 9 5.44+/-61 x 10(6) ml(-1); P < 0.001). The percentage motility differs significantly between the P pattern and both the G (41.2+/-17% vs. 50. 9+/-11%; P = 0.002) and the N patterns (41.2+/-17% vs. 53.4+/-11%; P = 0.001). Sperm morphology seems to be indicative of important function al characteristics of spermatozoa, for example motility and zona pellu cida binding.