Introduction: Although it is well established that all the aspects of male reproduction are hormonally regulated, the endocrine control of the ejaculatory reflex is still not completely clarified. Sex steroids, thyroid and pituitary hormones (oxytocin and prolactin) have been proposed to control the ejaculatory process at various levels, however, only a few reports are currently available. The aim of the present study is to evaluate the contribution of testosterone, TSH and prolactin (PRL) in the pathogenesis of ejaculatory dysfunction in a large series of subjects consulting for sexual dysfunction.
Methods: Among the 2652 patients studied, 674 (25.2%) and 194 (7.3%) reported premature and delayed ejaculation (PE and DE) respectively. Categorizing ejaculatory difficulties in an 8-point scale starting from severe PE and ending with anejaculation (0=severe PE, 1=moderate PE, 2=mild PE, 3=no difficulties, 4=mild DE, 5=moderate DE, 6=severe DE and 7=anejaculation).
Results: PRL as well as TSH levels progressively increased from patients with severe PE towards those with anejaculation. Conversely, the opposite was observed for testosterone levels. All of these associations were confirmed after adjustment for age (adj r=0.050, 0.053 and −0.038 for PRL, TSH and testosterone respectively; all P<0.05). When all hormonal parameters were introduced in the same regression model, adjusting for age, ΣMHQ (an index of general psychopathology) and use of selective serotonin reuptake inhibitor antidepressants, they were independently associated with ejaculatory problems (adj r=0.056, 0.047 and −0.059 for PRL, TSH and testosterone respectively; all P<0.05).
Conclusions: This study indicates endocrine system is involved in the control of ejaculatory function and that PRL, TSH and testosterone play an independent role.
Prague, Czech Republic
24 - 28 Apr 2010
European Society of Endocrinology