Recovery of sperm production following the cessation of gossypol treatment: a two‐centre study in China

A number of variables were investigated in 46 men who had stopped taking gossypol for their predictive association with the degree and time of recovery of spermatogenesis. 39 (87%) of the men were azoospermic at cessation of gossypol treatment. In those with sperm present the geometric mean concentration and total sperm count were 8.3 x 10 6/ml and 30.7 x 10 6 & respectively. 28 men (61%) recovered to a define threshold of spermatogenic function (sperm concentration or= 20 x 10 6/ml) with a median recovery time of 1.1 years. However 18 men (39%) had not recovered to this degree of spermatogenic function after a median follow-up of 1.9 years and of these 10 (22%) remained azoospermic. The influence of individual baseline variables on the time to defined recovery was examined using Kaplan-Meier curves for groups and their joint effect by Coxs regression model. The failure of recovery was strongly associated with longer treatment greater total dose of gossypol smaller testicular volume elevated FSH concentrations and to a lesser extent with greater body weight. (authors)