Distance from sexual health care, rather than socio-economic status, is the main factor preventing Australians from seeking checks for sexually transmitted infections, research suggests.

The study by Alfred Health's Melbourne Sexual Health Centre looked at more than 7000 patients and found those who need to travel further for support often leave worrying symptoms unchecked.

Delayed presentation heightens the risk of severe illness and infections spreading.

The research highlights how changes to access can help stop the spread of STIs, sexual health epidemiologist Eric Chow says.

"This is the first time we've measured these barriers in such a significant manner," Associate Professor Chow said.

"Improved local access to health care, alongside targeted strategies to encourage early health care-seeking among groups at increased likelihood of delay, such as those who live in the outer suburbs and regionally, is likely to make significant inroads into this issue and reduce the STI burden across the state."

In Victoria, some progress had already been made with the 2021 establishment of the Victorian Sexual Health Network in Melbourne's outer suburbs, Prof Chow said.

However, many still weren't aware of where they could receive treatment.

Gay and bisexual men sought health care earlier than heterosexual men, and people with marked symptoms or conditions such as genital herpes and gonococcal urethritis sought help earlier than patients with milder symptoms, the research showed.

"Despite this, many are still delaying seeking treatment, which can not only be harmful to the individual, but also puts any sexual partner they have at risk," Prof Chow said.

"The sooner an individual seeks treatment, the less likely they are to spread the infection."

Early treatment could also reduce health problems such as chronic pain, infertility and fetal and neonatal morbidity and mortality, Prof Chow said.