A sexually transmitted infection is an infection that spreads primarily through sexual contact; this can be through vaginal, oral or anal sex, or sometimes even just via external genital contact. Most of these infections may not immediately cause damage to your health or cause you to experience uncomfortable symptoms, but they may eventually cause you to develop serious health complications.
Bacterial STIs are more likely to cause serious health problems, however viral infections can also affect your health. Sexually transmitted infections can also be caused by parasites, although this is less common. The long-term complications a person is likely to develop usually depend on the type of infection, but there are certain similarities in the different groups of STIs.
It's imperative to treat STIs as soon as possible as they have the potential to affect female reproductive health, cause complications during pregnancy and potentially pose a threat to a baby during pregnancy or birth.
Research has shown that up to 40% of women develop pelvic inflammatory disease (PID). This increases a women's risk of developing an ectopic pregnancy, which is when a foetus develops outside the womb, which can be extremely dangerous to the mother. Around 50% of ectopic pregnancies can be attributed to pelvic inflammatory disease. STIs that have been linked to PID are chlamydia, gonorrhoea and bacterial vaginosis.
Viral STIs like genital warts and genital herpes are likely to cause complications during labour, however there are ways to avoid the infections spreading to the baby during delivery.
Bacterial infections can lead to urethral infections or urethritis in men that can eventually lead to kidney infections and even infertility. Untreated bacterial STIs can eventually lead to epididymitis, which is when the tube that transports sperm from the testicles becomes inflamed, leading to swelling of the scrotum and, ultimately, infertility. Some men have also been known to develop reactive arthritis as a result of chlamydia infections, although this is extremely rare.
Syphilis is an extremely serious sexually transmitted infection and will eventually lead to a number of serious complications in both men and women, causing serious neurological and cardiovascular problems as well as complications during pregnancy. A person with a syphilis sore is also five times more likely to contract HIV than a person without the infection.
Similarly, genital herpes can also increase the risk of contracting HIV, however this is largely due to the fact that it can cause internal ulcers that make the vaginal wall more vulnerable to infection during unprotected sexual intercourse. Bacterial infections like bacterial vaginosis have also been known to increase a person's vulnerability to contracting HIV.