These are the countries with the highest rates of contraceptive failure

Nations from Brazil to Egypt and Turkey are among developing countries with the highest rates of contraceptive failure, according to research released on Thursday on unintended pregnancies.

Some 74 million unintended pregnancies occur each year in developing nations, a third of which are due to failed contraception, said the New York-based Guttmacher Institute which studied 43 countries in Africa, Asia, Eastern Europe, Latin America and the Caribbean.

Exceptionally high rates of contraceptive failures were found in Benin, Bolivia, Brazil, Burundi, Dominican Republic, Egypt, Jordan, Kazakhstan, Paraguay and Turkey, it found.

The study by the research institute, which focuses on sexual and reproductive health, did not determine the precise causes of the particularly high incidences and said that would require additional analysis.

Withdrawal and rhythm methods were most likely to fail, while longer-acting methods such as intra-uterine devices (IUDs), subdermal implants and injection were least likely to do so, it found.

"Many factors, such as the quality of contraceptive services, availability of a range of methods, and the continuous availability of contraceptive supplies in that country, may contribute to this finding," Chelsea Polis, lead author of the study, told the Thomson Reuters Foundation.

Overall, the researchers found the lowest contraceptive failure rates in East Africa and South Asia.

The research pointed out that unintended pregnancies put women at risk of seeking abortions that are unsafe and illegal in many developing nations.

Separate research by the Population Council has found that the highest proportion of unintended pregnancies occur in Latin America and the Caribbean.

The Guttmacher researchers cautioned about the data quality from West Africa and stigma in some cultures as potentially affecting their analysis.