Table 3

Results from linear regression analyses of semen quality (adjusted β-coefficients) and serum reproductive hormones (percent change) among young, Danish men according to habitual alcohol intake (last week represented a typical week) or recent (the week preceding the visit) or binging during the past 30 days

Alcohol intake	N	Sperm concentration*† (million/mL)		Total sperm count*† (million)		Morphology†‡ (%)		N	Testosterone§¶ (nmol/L)		SHBG§¶ (nmol/L)		Free testosterone§¶ (pmol/L)
Alcohol intake	N	Β	95% CI	β	95% CI	β	95% CI	N	%	95% CI	%	95% CI	%	95% CI
Units in a typical week, N=553								Units the week preceding the visit, N=1194
0	121	−0.32	−0.62 to −0.03	−0.42	−0.86 to 0.01	−0.21	−0.54 to 0.12	242	−2.7	−8.5 to 3.5	−0.6	−8.6 to 6.9	−3.3	−9.1 to 2.6
1–5	92	Reference		Reference		Reference		193	Reference		Reference		Reference
6–10	71	−0.04	−0.38 to 0.3	−0.06	−0.56 to 0.45	−0.12	−0.49 to 0.26	154	3.3	−3.6 to 10.6	−3.0	−10.6 to 5.2	5.5	−1.4 to 12.9
11–15	80	−0.21	−0.54 to 0.12	−0.29	−0.77 to 0.20	−0.19	−0.56 to 0.18	160	2.0	−4.9 to 9.2	−3.1	−10.6 to 5.1	3.6	−3.1 to 10.7
16–20	62	−0.03	−0.39 to 0.33	−0.18	−0.70 to 0.34	−0.09	−0.46 to 0.29	130	3.0	−4.2 to 10.8	−2.1	−10.1 to 6.7	4.3	−3.0 to 12.0
21–25	45	0.25	−0.15 to 0.65	0.07	−0.52 to 0.65	−0.13	−0.55 to 0.29	92	7.3	−1.1 to 16.4	−0.2	−9.4 to 9.9	7.9	−0.3 to 16.9
26–30	25	−0.35	−0.83 to 0.14	−0.65	−1.37 to 0.08	−0.19	−0.71 to 0.34	71	1.0	−7.7 to 10.4	−9.0	−18.1 to 1.1	5.9	−3.1 to 15.5
31–35	14	−0.29	−0.92 to 0.33	−0.60	−1.51 to 0.31	−0.56	−1.19 to 0.06	47	6.1	−4.5 to 17.8	−9.8	−20.3 to 2.1	11.9	0.8 to 23.9
36–40	11	−0.33	−1.02 to 0.35	−0.73	−1.73 to 0.28	−0.54	−1.20 to 0.13	28	9.1	−4.2 to 17.8	−9.3	−22.2 to 5.7	16.0	2.1 to 31.7
>40	21	−0.39	−0.92 to 0.14	−0.54	−1.32 to 0.23	−0.46	−0.99 to 0.08	66	10.6	0.8 to 21.3	−12.0	−21.1 to −1.9	19.5	9.2 to 30.9
p trend**		0.02		0.01		0.02			0.01		<0.01		<0.01
Number of binge episodes during the past 30 days††
0	174	Reference		Reference		Reference		171	Reference		Reference		Reference
1–2	248	−0.01	−0.23 to 0.22	0.15	−0.18 to 0.48	0.07	−0.16 to 0.31	246	4.0	−2.5 to 10.8	7.9	0.1 to 16.4	1.0	−5.2 to 7.6
3–5	407	0.08	−0.13 to 0.29	0.26	−0.05 to 0.56	0.10	−0.12 to 0.31	401	6.2	0.1 to 12.6	4.1	−2.9 to 11.6	6.1	0.1 to 12.4
6–9	253	0.00	−0.23 to 0.23	0.08	−0.26 to 0.41	−0.04	−0.28 to 0.19	252	8.4	1.6 to 15.6	1.1	−6.7 to 9.2	10.2	3.4 to 17.5
>9	88	−0.02	−0.32 to 0.29	0.03	−0.41 to 0.47	−0.22	−0.52 to 0.08	89	13.0	3.8 to 23.1	−2.9	−12.1 to 7.5	17.2	7.8 to 27.6
p trend**		0.93		0.87		0.16			<0.01		0.31		0.01

*Adjusted for period of abstinence, smoking and body mass index (BMI) categorised according to table 2 (sperm morphology not adjusted for period of abstinence).
†Transformed by cubic root.
‡Counted for 904 men of whom 397 stated that last weeks alcohol intake represented a typical week.
§Adjusted to a time at 8.00, BMI and smoking.
¶Transformed by the use of natural logarithm and back transformed giving the percentages change.
**Test for trend was performed by inserting the categorical alcohol variable into the model assuming the association to be linear with 1–5 units weekly as reference and 0 units excluded.
††Binging defined as alcohol intake for more than 5 units on one occasion.