N: number of data; S.D.: standard deviation; NT: total kids born at birth; VOL: volume (ml); CON: sperm concentration (106/ml); MOT (%):
percentage of total motile sperm; NAR (%): percentage of sperm with normal apical ridge; ANR (%): percentage of abnormal sperm; VCL:
curvilinear velocity (m/s); VAP: average path velocity (m/s); VSL: straight-line velocity (m/s); LIN: linearity index (%); STR: straightness coefficient
(%); WOB: wooble coefficient (%); ALH: amplitude of lateral head displacement (m