The proportion of abortions that are considered unsafe is rising, according to a new report.

The numbers of abortions performed annually worldwide has held steady in recent years, but the proportion of abortions that are considered unsafe is rising, according to a new report from the Guttmacher Institute and the World Health Organization. The study also found that about one in five pregnancies were terminated in 2008 and that “restrictive abortion laws” do not seem to deter women from seeking the procedure.

One of the primary motivations for the study was to determine whether the number of unsafe abortions was increasing or decreasing, because these abortions are a major contributor to morbidity and mortality among women of childbearing age (between the ages of 15 and 44). Unsafe abortion has been defined by the WHO as “a procedure for termination of an unintended pregnancy done either by people lacking the necessary skills or in an environment that does not conform to minimum medical standards, or both.”

Under these circumstances, it’s not easy to find reliable statistics. So the researchers made estimates based on surveys of women, hospital records and whatever data could be gleaned from published studies. Statistics on safe abortions were taken primarily from government records and questionnaires filled out by government agencies.

Here’s some of what the researchers found:

— About 43.8 million abortions were performed around the world in 2008, up slightly from 41.6 million in 2003 but below the 45.6 million performed in 1995.

— Though the total number of abortions rose, the rate of abortions per 1,000 women of reproductive age fell slightly from 29 in 2003 to 28 in 2008. The difference was too small to be considered statistically significant. In 1995, the abortion rate was 35 per 1,000 women.

— In 2008, the abortion rate in the developing world — 29 per 1,000 women — was higher than in the developed world, where 24 out of 1,000 women terminated a pregnancy. The region with the highest abortion rate was Eastern Europe (43 per 1,000 women) and the lowest was western Europe (12 per 1,000 women). In North America, the abortion rate was 19 per 1,000 women, or 1.4 million overall, the researchers estimated.

— Worldwide, an estimated 49 percent of abortions were unsafe in 2008. The most perilous regions were Africa (where 97 percent of abortions there were unsafe), south Central Asia (65 percent) and Central and South America (where 100 percent of abortions were deemed unsafe).

— In the developed world, the proportion of pregnancies that were aborted fell from 36 percent in 1995 to 26 percent in 2008. In the developing world, the rate remained flat at 19 percent to 20 percent. Altogether, 21 percent of pregnancies around the world ended in abortion in 2008, essentially unchanged from 20 percent in 2003 and 22 percent in 1995.

— The abortion rate was higher in parts of the world with restrictive abortion laws than it was in regions with liberal abortion laws.

The researchers found evidence that more women were using the drug misoprostol for medical abortions (as opposed to more invasive surgical abortions). Though it can certainly be safer, it can also be dangerous if given by nonmedical personnel who don’t know what they’re doing, the researchers warned. “Complications such as prolonged and heavy bleeding and incomplete abortions are associated with use of incorrect dosages,” they wrote.

The researchers said they would have liked to examine data on the timing of abortions, since those performed early in pregnancy are generally safer. But information on gestational age was “scarce,” they wrote.

The report was published in Thursday’s edition of the Lancet. Fact sheets, maps and other information are available on the Guttmacher Institute website,