This is the VOA Special English Health Report.
A new study says fewer women in developing nations are dying of pregnancy-related causes. Researchers estimated how many mothers died during or soon after childbirth in one hundred eighty-one countries. They found a drop of more than thirty-five percent worldwide in the past thirty years.
By their count, the number fell from more than a half-million in nineteen eighty to about three hundred forty-three thousand in two thousand eight. That year, about two hundred fifty mothers died for every one hundred thousand live births worldwide.
The researchers say the maternal death rate has been falling almost one and a half percent a year since nineteen ninety. Earlier reports suggested little change between nineteen eighty and nineteen ninety, but the new study disputes that.
The researchers used government records, medical records, surveys and other information. They developed new methods to get what they say are the best estimates yet for almost every country.
They say the progress is a result of greater efforts to reduce maternal deaths.
Christopher Murray at the University of Washington's Institute for Health Metrics and Evaluation in Seattle led the study. He says more education of women in developing countries has helped lower maternal death rates. More of them are giving birth in hospitals.
Doctor Murray says lower fertility rates around the world, combined with higher earnings, are also reducing deaths.
The nations found to have the biggest reductions were Egypt, Ecuador and Bolivia. The researchers say China also had a sharp drop.
But since nineteen ninety maternal death rates have risen in some countries. Zimbabwe, for example, had a five and one-half percent increase per year. Afghanistan, India, Pakistan, Nigeria, the Democratic Republic of Congo and Ethiopia also had increases.
H.I.V. has slowed the progress in reducing maternal deaths. The study linked almost one in every five such deaths in two thousand eight to the virus that causes AIDS.
The researchers say maternal deaths rates have also increased in some wealthy countries. They found the number in the United States rose almost forty-two percent since nineteen ninety. Countries such as Canada and Norway also had increases. Doctor Murray says at least part of the increase is likely the result of better record keeping.
The study also included the University of Queensland in Australia. The report is in the Lancet.
maternal death rate：孕产妇死亡率
University of Washington's Institute for Health Metrics and Evaluation in Seattle：西雅图华盛顿大学健康指标和评估研究所