It is important to get regular sexual health checkups because some STIs can be asymptomatic. This means that they are not presenting with any symptoms and as such you may have one without even knowing it. Furthermore, you could be passing it on to your sexual partners again without knowing that you are doing so.
PREVENTION AGAINST STIs
Whilst some STIs can be vaccinated against, such as Hepatitis A and B or the Human Papillomavirus (HPV), others can be difficult to avoid. Over time there has been a significant increase in the amount of STIs being diagnosed, and amongst most populations (i.e., gay men and both heterosexual men and women). The best way to prevent contracting an STI is to use condoms and water based lube when having sex, and to get a regular sexual health check up. This may not prevent everything, but at least you will know and get treated easily. Get tested, get treated, no drama!
For more information about particular STIs, in terms of how they are transmitted, diagnosed, treated and prevented, check out: