Sexual coercion, social disadvantages and rural residence are associated with unplanned pregnancies, new research shows.

Most unwanted or unexpected pregnancies are linked to sexual coercion, social disadvantages, living in rural areas and men being born overseas, Australian researchers say.

A national survey was conducted on women and men aged 18 to 51 years, and data was analysed from 2235 questionnaires.

About 59 per cent of participants had been pregnant or had a partner who had been pregnant, and 40 per cent of those people had experienced an unintended pregnancy.

Most people believed contraception was a shared responsibility and could easily access affordable contraception, but 10 per cent still used withdrawal, which was the third most common method after the use of condoms and taking the pill.

The study found that in rural areas a lack of access to contraceptives could contribute to unintended pregnancies, and socioeconomic health inequality remained a key issue.

It also found that men born overseas were significantly more likely to be involved in unintended pregnancies than men born in Australia, but the reasons were unclear.

Lastly, they found that past experiences of sexual coercion doubled the risk of unintended pregnancies.

The study, which was led by Heather Rowe from Monash University, concluded public health policy and health service initiatives should focus on the prevention of sexual coercion and the reduction of social and geographic inequality.