Considering the shortcomings of these former PE definitions, Waldinger and Schweitzer highlighted the importance of distinguishing PE as a “complaint” from PE as a “syndrome” [24]. These authors draw attention to the misconception that PE has always been regarded as a male sexual syndrome, although it can also be a normal variation of normal ejaculatory response [29]. Furthermore, in addition to the previously defined lifelong and acquired PE syndromes [30], they proposed the existence of two additional PE syndromes, refered to as natural variable PE and premature-like ejaculatory dysfunction. Both of these new syndromes are assumed to be responsible for the previously reported high prevalences of PE [29]. On the other hand, PE complaints of patients with these latter two syndromes are not as severe as lifelong and acquired PE patients, therefore they do not actively seek treatment although they appear in epidemiologic studies [22, 26, 29, 31, 32].

A recent cross-sectional field survey investigated the prevalence of these four PE syndromes with strata being selected by the proportional (stratified) sampling method [22]. Of the 2,593 men involved, 2.3, 3.9, 8.5, and 5.1 % were diagnosed as having lifelong, acquired, natural variable PE syndromes, and premature-like ejaculatory dysfunction, respectively. This confirmed that the prevalence of actual PE patients requiring medical treatment is much lower than the prevalence of men who occasionally complain about ejaculating too rapidly. However, it is noteworthy that although the International Society for Sexual Medicine (ISSM) managed to develop an evidence-based definition for lifelong PE [25], such a definition has not yet been generated for other PE syndromes. Therefore, the remaining three PE syndromes are considered to be provisional but are also thought to be beneficial for health-care professionals in addressing the concerns of men with PE complaints that do not meet the ISSM criteria for lifelong PE [33].