More than 25 million unsafe abortions, or 45 percent of all abortions, were performed worldwide each year from 2010 to 2014, according to a new analysis by the Guttmacher Institute and the World Health Organization.

"Increased efforts are needed, especially in developing countries, to ensure access to safe abortions," concluded the authors, led by WHO physician Bela Ganatra, a reproductive-health expert.

The report, published in the Lancet, updates a 2012 overview, when the researchers estimated that there were 43.8 million abortions worldwide, half of them unsafe.

The new analysis distinguished, for the first time, among three categories of abortion: safe, meaning a trained provider used a method recommended by WHO; less-safe, meaning either the provider was untrained or the method was outdated; and least-safe, meaning an untrained provider used dangerous methods. Those methods included inserting a foreign body such as a twig or coat hanger into the uterus, or having the patient drink caustic concoctions.

In developed countries, nearly 88 percent of abortions were safe — meaning less-safe abortions also occurred in these nations, primarily in Eastern Europe. In North America, an estimated 1 percent of abortions were less safe.

The report comes at time when Planned Parenthood, the nation's leading abortion provider, has faced repeated Republican Party efforts to cut its funding for all services, including family planning and gynecological exams.

Other findings from the report:

  • There were 55.7 million abortions each year of the study. Almost all the unsafe abortions (97 percent) occurred in developing countries, particularly parts of Africa and Latin America.
  • In the 67 countries where abortion is banned or allowed only to save the woman's life, just a quarter of procedures were safe.
  • In the 57 countries where women can choose to terminate pregnancy, including the U.S., about 87 percent of abortions were safe.
  • Although the analysis did not directly estimate the number of abortion-related deaths, it did calculate by region the proportion of maternal deaths that were due to abortion. Western and Middle Africa had the worst rates, with more than 400 deaths per 100,000 abortions.