Association of Endogenous Seminal L-Carnitine Levels with Post-Thaw Semen Parameters in Humans
Table 2
Semen parameters in fresh and post-thaw samples according to high and low endogenous seminal L-carnitine levels.
Variable
Fresh samples
Post-thaw samples
Fresh vs post-thaw samples
Low seminal L-carnitine levels# (≤38.8 µg/ml)
High seminal L-carnitine levels# (>38.8 µg/ml)
Low seminal L-carnitine levels# (≤38.8 µg/ml)
High seminal L-carnitine levels# (>38.8 µg/ml)
Low seminal L-carnitine levels# (≤38.8 µg/ml)
High seminal L-carnitine levels# (>38.8 µg/ml)
n
Median (min–max)
n
Median (min–max)
p
n
Median (min–max)
n
Median (min–max)
p
p
p
Endogenous seminal L-carnitine (µg/ml)
63
25 (6–38.8)
62
68 (39–220)
<
—
—
—
—
—
—
—
Semen volume (ml)
63
4 (2–8)
62
3 (1–7)
—
—
—
—
—
—
—
Sperm concentration (106/ml)
63
23 (5–73)
62
56 (11–239)
<
—
—
—
—
—
—
—
Total sperm count (106)
63
81 (14–413)
62
187 (25–521)
<
—
—
—
—
—
—
—
Rapid progressive sperm motility (a, %)
53
17 (2–42)
57
28 (4–55)
63
7 (0–27)
62
12 (2–26)
<
<
Progressive sperm motility (a + b, %)
53
35 (11–59)
57
43 (15–63)
0.037
63
17 (0–39)
62
25 (3–40)
<
<
Total sperm motility (a + b + c, %)
53
48 (18–70)
57
54 (21–74)
0.113
63
27 (1–51)
62
36 (5–51)
<
<
<
Immotile sperm (d, %)
53
52 (30–82)
57
46 (26–79)
0.113
63
73 (49–99)
62
65 (49–95)
<
<
<
Sperm vitality (%)
63
57 (19–88)
62
63 (30–80)
0.027
63
34 (4–53)
62
38 (16–58)
0.051
<
<
Normal sperm morphology (%)
61
8 (1–31)
59
8 (1–32)
0.771
61
7 (1–29)
60
7 (0–24)
0.862
0.510
0.032
Sperm head defects (%)
61
88 (66–96)
59
87 (56–99)
0.429
61
88 (59–99)
60
86 (72–99)
0.134
0.648
0.789
Sperm neck midpiece defects (%)
61
28 (9–55)
59
26 (3–55)
0.825
61
32 (3–67)
60
30 (4–61)
0.220
0.127
Sperm principal piece defects (%)
61
13 (3–31)
59
12 (3–26)
0.676
61
15 (5–37)
60
14 (6–36)
0.213
<
Sperm DNA fragmentation (%)
63
15 (6–88)
62
14 (2–54)
0.204
62
22 (8–62)
62
20 (6–48)
0.192
<0.001
Seminal sORP (mV)
63
41 (3–172)
61
41 (3–97)
0.601
62
66 (21–118)
62
55 (19–146)
<
<
#The population was categorized in two groups according to the 50th percentile of endogenous seminal L-carnitine levels. sORP, static oxidation-reduction potential. p values ≤ 0.01 were considered statistically significant. Mann–Whitney U test was used to compare variables in samples with low and high seminal L-carnitine levels. Wilcoxon signed-rank test was used to compare semen quality variables in fresh and post-thaw samples.
