Only about half of people with a sexually transmitted disease would tell a new partner about their infection before having sex, a new review finds.

The team said their review of the findings of several previous studies showed the "complex" nature of revealing an STI diagnosis to a partner prior to engaging in sexual activity. The research shows that only around half or fewer people felt able to disclose their diagnosis to a partner before sex.

It's common for people with a STI to feel no obligation to disclose it, according to the research.