Since 2008, the obstetrician-gynecologist has been traveling to sub-Saharan Africa. While working in Zambia, she saw gynecologic units in the hospital filled with women admitted with heavy bleeding or life-threatening infections, she said.

The women often would remain tight-lipped about why they were hemorrhaging, but Haddad said that it was clear to her and the Zambian clinicians what was happening. Some of the women had unsafe abortions and were facing serious complications, she said.

"This is a public health priority and I don't think it's been placed on that level and given the attention that it needs," said Haddad, associate professor in the department of gynecology and obstetrics at Emory University School of Medicine.

A new study finds nearly half of all 55.7 million estimated abortions around the world each year between 2010 and 2014 were performed in an unsafe manner, putting women at risk for serious complications.

, The study published Wednesday in the journal The Lancet , suggests that unsafe abortions are still a major health problem globally, especially in developing countries.

"These are the first global estimates to show the distribution of the abortions across three safety categories," said Dr. Bela Ganatra, a scientist at the department of reproductive health and research at the World Health Organization and lead author of the study.

"For the first time, we actually tried to determine the conditions under which abortions take place, how, who, where. This allows us to develop a better understanding of actions needed," she said.

a pregnancy that is terminated either by someone who lacks the necessary medical skills or in an environment that does not conform to minimal medical standards, or both. Based on the WHO definition, an unsafe abortion results froma pregnancy that is terminated either by someone who lacks the necessary medical skills or in an environment that does not conform to minimal medical standards, or both.

Unsafe abortions can lead to complications , such as heavy bleeding, infection, damage to genitals or internal organs, or an incomplete abortion, such as when all of the pregnancy tissue is not removed from the uterus, according to WHO.

Complications related to unsafe abortions sometimes can be fatal

"I think that there's no question that unsafe abortion continues to be one of the leading causes of maternal mortality and morbidity, and importantly this is preventable," said Haddad, who was not involved in the new study. Abortions performed by trained providers through evidence-based approaches are safe, she said.

Counting unsafe abortions

The study, conducted by an international team of researchers at WHO and Guttmacher Institute, involved 150 pieces of data from 61 countries on both safe and unsafe abortions performed around the world between 2010 and 2014.

The information was collected from previous surveys and studies, bibliographic databases, and ministries of health or national statistical organizations.

The researchers analyzed the data to determine how many abortions fit within the WHO's definition of "unsafe."

They found that, in total, about 55.7 million abortions occurred annually worldwide between 2010 and 2014. Among those abortions, about 25.1 million were performed in unsafe circumstances each year -- with about 17.1 million being "less safe" and 8 million being "least safe," the researchers found.

Overall, almost all abortions in developed countries were deemed safe, whereas roughly half of those in developing countries were safe, according to the findings.

"Among the developed regions, the distributions of abortions across the safety categories were similar with the majority of abortions being performed under safe conditions, except for Eastern Europe, where 14% were less safe," Ganatra said.

"While both Africa and Latin America had low proportions of abortions that were carried out in safe conditions, it was striking to note that among the unsafe abortions, the vast majority in the Latin America region were performed under less safe conditions (59.7%) while in Africa the majority of unsafe abortions were performed under the least safe conditions (48%)," she said. "It is also important to note that women undergoing abortions in Africa had the highest risk of dying from a least safe abortion."

Eastern Asia, including China, had a distribution similar to developed regions, Ganatra said. Yet in South-Central Asia, less than one in two abortions were safe.

"The paper did not examine country specific data, but other evidence shows that the same disparities exist within countries as well -- between rural and urban, rich and poor," Ganatra said.

Such a disparity often emerges when any health outcome is measured in developed versus developing regions, but safe abortion care is possible in developing countries, Ganatra said.

She pointed to Nepal Ethiopia , and Uruguay as examples of countries that have made progress in expanding access to safe abortion procedures, she said.

A separate study found that in 2012 almost 7 million women were treated for complications of unsafe abortions in the developing world. The study published in BJOG: An International Journal of Obstetrics and Gynaecology in 2015.

'She really saw no other option for herself'

The researchers wrote in the new study, "this analysis suggested that unsafe abortion is still a major problem in developing countries and that progress towards safer abortion is needed, even in some developed countries."

Yet the study came with several limitations due to the dearth of data.

"They're basing their data on other studies and numbers that are available and those numbers that are out there are limited based on their ability to estimate the true incidence," Haddad said. "So, they're likely underestimates."

The researchers themselves noted in the study that, in general, empirical data on abortions were scarce, especially in countries where abortions were legally restricted, stigmatized or less likely to be reported.

"This study gives us the first global estimates of how often women are able to find safe abortions, even if they are not getting legal abortions. It is very difficult to accurately measure abortion and abortion-related mortality, especially in countries where it is illegal. These may be the best estimates possible and yet still be an undercount," said Diana Greene Foster, professor of obstetrics, gynecology, and reproductive sciences at the University of California, San Francisco, who was not involved in the new study.

"I have studied women who are unable to get a legal abortion in six countries: the United States, Colombia, Tunisia, South Africa, Bangladesh and Nepal. Even where abortion is supposed to be legal and available, many women are unable to access services within the medical system," she said. "Some women facing an unwanted pregnancy go on to get illegal, but safe, abortions, some get illegal unsafe abortions and some carry the unwanted pregnancy to term."

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Emory University's Haddad said that she remembers traveling to Nepal as a medical student around 2005, after the South Asian country liberalized some of its abortion restrictions. Knowledge of those reduced restrictions was not widespread, she said.

"We had a woman who came in the clinic who was right above the gestational age limit to which abortion was legal. ... It was very clear that she was seeking any way to end the pregnancy," Haddad said. "She spoke openly about suicide as an option rather than continuing with the pregnancy."

The woman was desperate because she was raped while her husband was away and she feared what would happen when her husband would return to find her pregnant, Haddad said.

"She really saw no other option for herself. ... I don't know whatever happened with her, but I can't imagine that it was good," Haddad said.

"It spoke to me because she did nothing on her own to get herself in that situation and saw no way out of it, and there was nothing I could do," she said. "And unfortunately, irrelevant of what people think of abortion, you can't ignore the fact that this is a crisis that is avoidable."