Table 1 General characteristics of the three age groups studied

Patients

975

407

292

276

Age (years)

37.5 ± 6.7

31.7 ± 2.7

37.8 ± 1.3

45.8 ± 5.2

Fathered at least one child

36%

23.1%^a,b

33.6%^a,c

57.7%^b,c

(351/975)

(94/407)

(98/292)

(159/276)

Duration of infertility (years)

3.7 ± 3.3

3.0 ± 2.2^d,e

3.6 ± 2.9^d,f

5.0 ± 4.5^e,f

Abstinence (mean ± SD)

3.5 ± 1.3

3.6 ± 1.3

3.5 ± 1.4

3.5 ± 1.3

Sperm Parameters* (mean ± SD)

-volume (ml)

2.7 ± 0.13

2.8 ± 1.2

2.9 ± 1.2

2.6 ± 1.4

-total sperm count x10⁶/ml

61.2 ± 53.8

62.9 ± 53.0

64.8 ± 53.2

56.0 ± 51.8

-motility (rapid+slow progression)%

58.9 ± 17.9

59.9 ± 17.3

57.6 ± 18.7

54.4 ± 19.2

-leukocytes (x10⁶)

0.4 ± 0.9

0.4 ± 0.7

0.4 ± 1.2

0.4 ± 0.7

-vitality (%)

66.5 ± 15.1

68.7 ± 14.1

65.6 ± 15.7

64.2 ± 15.3

Sperm DNA fragmentation (%)

17.1 ± 9.6

15.6 ± 9.1^g,h

18.1 ± 9.7^g

18.3 ± 10.2^h

Varicocele (%)

17

14.7

18.5

18.8

(166/975)

(60/407)

(54/292)

(52/276)

Tobacco use (%)

11.9

13.8

10.3

10.9

(116/975)

(56/407)

(30/292)

(30/276)

Regular alcohol use (%)

64.2

65.3

66.4

60.1

(626/975)

(266/407)

(194/292)

(166/276)

Vitamin supplement use (%)

15.5

15.5

13.7

17.4

(151/975)

(63/407)

(40/292)

(48/276)