Table 1. Distributions of head length, width, area, perimeter, acrosomal head coverage, and length/width (L/W) and perimeter/area (P/A) ratios for spermatozoa in semen samples and after swim-up: all samples considered.

	Median	Mean	Max	Min	Range	5% centiles	95% centiles
Spermatozoa in semen (central tendency of 72 samples)
Length (μm)	4.39	4.37	5.00	3.66	1.33	3.85	4.88
Width (μm)	2.79*	2.75	3.15	2.09	1.06	2.39	3.08
Area (μm2)	9.77*	9.86	12.05	7.09	4.97	8.46	11.20
Perimeter (μm)	12.52*	12.48	13.80	11.06	2.74	11.27	13.49
Acrosome (%)	47.50	47.60	59.40	38.00	21.40	39.40	56.10
L/W	1.57	1.59	2.10	1.34	0.76	1.40	1.88
P/A	1.28*	1.27	1.61	0.82	0.79	1.18	1.40
Spermatozoa after swim-up (central tendency of 72 samples)
Length (μm)	4.42	4.40	5.03	3.78	1.26	3.96	486
Width (μm)	2.84	2.82	3.27	2.44	0.83	2.53	3.14
Area (μm2)	10.29	10.20	12.15	8.06	4.09	8.57	11.60
Perimeter (μm)	12.90	14.04	22.08	11.07	11.01	11.49	21.35
Acrosome (%)	48.20	48.20	57.20	35.40	21.80	3840	55.30
L/W	1.56	1.56	1.88	1.34	0.54	1.37	1.78
P/A	1.25	1.38	1.43	1.11	0.32	1.15	1.35

^*P < 0.05, compared with sources of spermatozoa after swim-up.