OBJECTIVETo investigate the semen quality and its influencing factors in preconception males in Nanjing area so as to provide some evidence for working out effective intervention measures.

METHODSTotally 687 men receiving preconceptional physical examination were enrolled in this study. A questionnaire survey was conducted among the subjects along with an analysis of their semen quality.

RESULTSThe median of sperm concentration was 63.3 x 10(6)/ml (95% CI [19.88-119] x 10(6)/ml). The median of grade a sperm was 33.03% (95% CI [19.38-55.05]%), that of grade a + b sperm was 52.08% (95% CI [39.53-69.37]%), and that of teratosperm was 91.75% (95% CI [69-100]%). The median concentration of seminal plasma PMN-elastase was 195.55 ng/ml (95% CI [76.16-3330.38] ng/ml) and that of seminal plasma zinc was 7.62 μmol/L (95% CI [1.5-23, 45] μmol/L). The positive rates of Ureaplasma urealyticum (UU), Chlamydia trachomatis (CT), and Gardnerella vaginalis (GV) were 42.4%, 0.3%, and 2.4%, respectively. The median of sperm DNA fragmentation index (DFI) of those whose wives had a history of adverse pregnancy was 20.25% (95% CI [2.15-68.25]%). Multivariate logistic regression analysis suggested that mental stress (OR 1.567, 95% CI [1.081-2.27]) and sedentariness (OR 1.772, 95% CI [1.211-2.592]) were independent risk factors for asthenospermia.

CONCLUSIONThe sperm quality of preconception males in Nanjing area is not encouraging, and it can be improved by changing undesirable lifestyle and reducing mental stress.