The density of human semen and the validation of weight as an indicator of volume: a multicentre study

A multi-centre study was undertaken to: a/ determine the density of human semen, and b/ assess the validity of measuring semen volume either volumetrically or gravimetrically. Semen samples from four clinical categories (azoospermia following vasectomy, azoospermia without vasectomy, oligozoospermia (20×106/ml)) had similar densities (one-way ANOVA: F(3,180)=1.25, not significant), being close to 1.0 g/ml when taken to one decimal place. Measurement of semen volume was then made with either a graduated pipette or by weighing and assuming a density of 1 g/ml. A comparison of the two methods gave an excellent correlation, with a gradient of 1.0571 and a coefficient of determination (R2) of 0.98 (p