Abortion rates have declined significantly over the last 25 years in developed countries and are at a historic low. But in developing countries, where many abortions are unsafe, rates have remained level, highlighting the urgent need for better access to modern contraception (eg, hormonal pill, implants, IUDs) to reduce unwanted pregnancies and abortions.
The new global and regional estimates of abortion incidence from the Guttmacher Institute and WHO, published in The Lancet, also suggest that restrictive abortion laws do not limit the number of abortions. Indeed, in countries where abortion is strongly legally restricted , and often performed under unsafe conditions, the incidence of abortion is estimated to be as high as the incidence in countries where it is legal.
"In developed countries, the continued fall in abortion rates is largely due to increased use of modern contraception that has given women greater control over the timing and number of children they want", explains lead author Dr Gilda Sedgh at the Guttmacher Institute, New York, USA. "In developing countries, however, family planning services do not seem to be keeping up with the increasing desire for smaller families. More than 80% of unintended pregnancies are experienced by women with an unmet need for modern methods of contraception, and many unwanted pregnancies end in abortion."
The study used abortion data from nationally representative surveys, official statistics, and other published and unpublished studies, along with information on the level of unmet need for contraception and the prevalence of contraceptive use, by type of method. The researchers used a statistical model to estimate levels and trends in abortion incidence for all major world regions and subregions from 1990 to 2014.
Between 1990 and 2014, the developed world's annual abortion rate per 1000 women of childbearing age (15-44 years) dropped from 46 to 27, mainly as a result of the rate in Eastern Europe more than halving (88 per 1000 women to 42) as modern contraceptive methods became more widely available. However, in the developing world the abortion rate has remained virtually unchanged, declining from 39 to just 37 (table 1). Worldwide, on average 56 million abortions took place each year in 2010-2014.
Over the last 25 years, Eastern Europe has seen the biggest drop in abortion rates (88 to 42 per 1000 women), but rates also fell in Southern Europe (38 to 26), Northern Europe (22 to 18), and North America (25 to 17). The overall abortion rate in Africa, where the vast majority of abortions are illegal, remained virtually unchanged--33 abortions per 1000 women in 1990-94 to 34 per 1000 in 2014.
The estimated worldwide proportion of pregnancies that end in abortion has been fairly stable over time, with the world average in 2010-14 being one in four (25%). In developed countries, abortion has declined as a proportion of all pregnancies from 39% in 1990-94 to 28% in 2010-14, whereas in developing countries it increased from 21% of pregnancies in 1990-94 to 24% in 2010-14. In Latin America, a region with highly restrictive abortion laws, one in three pregnancies (32%) ended in abortion in 2010--2014, higher than any other region (table 3).
Importantly, the study found that abortion occurred at similar rates in countries where it is legal and where it is prohibited. For example, in countries where abortion is prohibited altogether, or allowed only to save a woman's life, the rate is 37 abortions per 1000 women, compared with 34 where it is legally permitted on request (table 4).
"More women living in countries with the most restrictive abortion laws have an unmet need for contraception--that is, they want to avoid getting pregnant but are not using a method of family planning--than women in countries with more liberal laws, and this adds to the incidence of abortion in countries with restrictive laws", says Dr Sedgh 
The authors note that the new estimates override previous global estimates from 1995, 2003 and 2008. Because of the limited availability of data on abortion in developing countries, the estimates in these regions have wide measures of uncertainty.
"Estimates of the proportion of abortions that are unsafe are under development but we already know nearly 300 million dollars are spent each year on treating the complications from unsafe abortions", adds co-author Dr Bela Ganatra, a scientist from the World Health Organization, Geneva, Switzerland. "The high rates of abortion seen in our study also provide further evidence of the need to improve and expand access to effective contraceptive services. Investing in modern contraceptive methods would be far less costly to women and society than having unwanted pregnancies and unsafe abortions."
Writing in a linked Comment, Professor Diana Greene Foster at the University of California in the USA discusses the new finding that abortion rates are the similar in settings where it is legally available on request and where it is illegal under all circumstances, she says, "The obvious interpretation is that criminalising abortion does not prevent it but, rather, drives women to seek illegal services or methods. But this simple story overlooks the many women who, in the absence of safe legal services, carry unwanted pregnancies to term...Women who live in countries where abortion is illegal often have little access to the whole range of family planning services, including contraceptive supplies, counselling, information, and safe abortion. As a consequence of increased rates of unintended pregnancy and unsafe abortion, such women face an increased risk of maternal mortality and bear children that they are not ready to care for and often cannot afford."
NOTES TO EDITORS:
This study was funded by UK Government, Dutch Ministry of Foreign Affairs, Norwegian Agency for Development Cooperation, The David and Lucile Packard Foundation, UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction.
 The countries where abortion is illegal or permitted only to save a woman's life are: South America--Brazil, Colombia, Chile, Dominican Republic, El Salvador, Guatemala, Haiti, Honduras, Mexico, Nicaragua, Panama, Paraguay, Venezuela; Sub-Saharan Africa--Angola, Benin, Central African Republic of Chad, Congo, Côte d'Ivoire, Democratic Republic of Congo, Gabon, Guinea- Bissau, Kenya, Lesotho, Madagascar, Mali, Mauretania, Mauritius, Niger, Nigeria, Senegal, Somalia, Tanzania, Togo, Uganda; Middle East and North Africa--Afghanistan, Egypt, Iran, Lebanon, Libya, Oman, Sudan (r), Syria, United Arab Emirates, Yemen; Asia and Pacific--Bangladesh, Indonesia, Laos, Myanmar, Papua New Guinea, Philippines, Sri Lanka. Europe: Ireland, Malta.
 Quotes direct from authors and cannot be found in text of Article.
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