Table 1. Descriptive characteristics of standard sperm parameters of study subjects.

Sperm parameters	unit	Infertile men (n = 344)		Fertile men (n = 124)		p value
		Mean ± SD	% of normal values*	Mean ± SD	% of normal values
Concentration	×106/mL	39.9 ± 37.5	72.6	85.4 ± 72.8	94.4	<10−5
Total number of spermatozoa	×106	167 ± 204	70.2	304 ± 299	97.2	<10−5
Morphologically normal spermatozoa	%	4.5 ± 4.7	43.5	10.2 ± 7.1	90.2	<10−5
Progressive motility	%	39.8 ± 21.8	62.2	47.5 ± 17.2	85.5	0.0007
Non-progressive motility	%	13.5 ± 10.4	–	18.8 ± 9.7	–	<10−5
Total motility	%	53.0 ± 20.0	77.6	66.4 ± 14.8	96.0	<10−5
Immotile spermatozoa	%	47.0 ± 20.0	–	33.6 ± 14.8	–	<10−5

SD–standard deviation; p value calculated by means of Mann-Whitney U-test; *according to the WHO guidelines.