Sexually Transmitted Infections (STIs)

STIs are transmitted from infected individuals to their sexual partners during vaginal, anal, or oral sex. They are caused by microorganisms, including bacteria, viruses, and parasites.

Anyone can contract an STI if they have sex with an infected person. Transmission is more likely without condom use or with multiple sexual partners. Even those with a single partner may acquire an STI if that partner has other sexual contacts and becomes infected.

STIs often remain asymptomatic for months or years. In such cases, only specific tests can reveal the infection. When symptoms do occur, they may appear shortly after sexual contact or take weeks, months, or years to develop. Sometimes, symptoms disappear without treatment, but the infection remains in the body.

Common signs and symptoms include abnormal discharge from the vagina, penis, or anus; pain or burning during urination; sores or blisters in the genital area; itching or irritation; and pain in the lower abdomen or during sex.

If untreated, some STIs can lead to serious complications: pelvic inflammatory disease, epididymitis, orchitis, infertility, cancer of the cervix, penis, or anus. In pregnant women, STIs may cause miscarriage, premature birth, or transmission to the fetus, resulting in congenital malformations or neonatal disease.

Examples of STIs include:
Gonorrhoea: [download information leaflet from the Portuguese Society of Dermatology and Venereology]
Chlamydia: [download information leaflet from the Portuguese Society of Dermatology and Venereology]
Genital Herpes: [download information leaflet from the Portuguese Society of Dermatology and Venereology]
Human Papillomavirus Infection: [download information leaflet from the Portuguese Society of Dermatology and Venereology]
Pubic Lice: [download information leaflet from the Portuguese Society of Dermatology and Venereology]
Syphilis: [download information leaflet from the Portuguese Society of Dermatology and Venereology]