Sexually transmitted diseases (STDs) have been a public health issue in many developing countries, especially in Vietnam. Unsafe sex is considered to be one of the main causes to increase infected person. Therefore, we conducted a study on 3005 men who presented to the Andrology and Sexual Medicine Units of Hanoi Medical University Hospital to analyze the correlation between sexual behaviors and sexually transmitted diseases in men. The result showed that the mean age at first sex (AFS) was 21 years old. The median number of stable sexual partners was 2, the overall rate of STDs was 9.95%, in particular, the proportion of STDs in single men was higher than the married group (11.8% and 7.5%, p < 0.001), men having first intercourse before 25 years old had the rate of STDs was higher compared with their counterpart (21.1% vs. 13.2%, p = 0.002). Subjects with multiple unstable sexual partners were 2.11 times more likely to be infected with STDs, and the risk of infecting STDs would rise 6% for each additional sex partner.

Premature ejaculation (PE) is the most common reported sexual complaint in men. It is believed that PE is associated with sexual behavior such as early sexual experience, novelty of partners or frequencies of intercourse. Therefore, to examine the association of PE and sexual behaviors in men, a case-control study was conducted with a total of 418 clients Subjects were interviewed for general health status, sexual behaviors, IELT and requested to complete the premature ejaculation diagnostic tool (PEDT). DSM-IV-TR criteria were applied for the diagnosis of PE. Those who diagnosed with PE(+) and PEDT score ≥ 11 belonged to the PE group; those diagnosed with PE(-) and PEDT < 11 belonged to the non-PE group. The results indicated that no significant difference was noted regarding demographic features in the 2 groups. Normal men had a more frequent sexual life compared with PE patients (9.71 ± 6.09 and 6.62 ± 5.44 episodes of sexual intercourses per month, respectively with p < 0.001. Subjects who were single or circumcised had higher prevalence of PE than married or uncircumcised men. Multivariable logistic analysis elucidated that circumcision, number of lifetime sexual partners and sexual frequencies were associated factors of PE. In conclusion, PE is a common sexual dysfunction in men. It was found to be significantly associated with circumcision and frequencies of sexual intercourse. Medical history taking of PE patients should include these sexual behavior factors.