For the first time in decades, researchers are reporting a significant drop worldwide in the number of women dying each year from pregnancy and childbirth, to about 342,900 in 2008 from 526,300 in 1980. The findings, published in the medical journal The Lancet, challenge the prevailing view of maternal mortality as an intractable problem that has defied every effort to solve it. 'The overall message, for the first time in a generation, is one of persistent and welcome progress,' the journal's editor, Dr. Richard Horton, wrote in a comment accompanying the article, published online on Monday. The study cited a number of reasons for the improvement: lower pregnancy rates in some countries; higher income, which improves nutrition and access to health care; more education for women; and the increasing availability of 'skilled attendants' -- people with some medical training -- to help women give birth. Improvements in large countries like India and China helped to drive down the overall death rates. But some advocates for women's health tried to pressure The Lancet into delaying publication of the new findings, fearing that good news would detract from the urgency of their cause, Horton said in a telephone interview. 'I think this is one of those instances when science and advocacy can conflict,' he said. Horton said the advocates, whom he declined to name, wanted the new information held and released only after certain meetings about maternal and child health had already taken place. He said the meetings included one at the United Nations this week, and another to be held in Washington in June, where advocates hope to win support for more foreign aid for maternal health from Secretary of State Hillary Rodham Clinton. Other meetings of concern to the advocates are the Pacific Health Summit in June and the U.N. General Assembly meeting in December. 'People who have spent many years committed to the issue of maternal health were understandably worried that these figures could divert attention from an issue that they care passionately about,' Horton said. 'But my feeling is that they are misguided in their view that this would be damaging. My view is that actually these numbers help their cause, not hinder it.' He said the new study was based on more and better data and more sophisticated statistical methods than were used in a previous analysis by a different research team that estimated more deaths, 535,900 in 2005. The authors of the earlier analysis, published in The Lancet, in 2007, included researchers from UNICEF, Harvard, the World Bank, the World Health Organization and the Johns Hopkins School of Public Health. The World Health Organization still reports about half a million maternal deaths a year, but it is expected to issue new statistics of its own this year. The new report comes from the University of Washington and the University of Queensland in Brisbane, Australia, and was paid for by the Bill and Melinda Gates Foundation. A spokesman for UNICEF said it had no comment on the new findings, and there was no response to messages that were left late Tuesday for WHO officials. Dr. Christopher J.L. Murray, the director of the institute for health metrics and evaluation at the University of Washington, in Seattle, and an author of the study, said, 'There has been a perception of no progress.' But, he said, 'some of the policies and programs pursued may be having an effect, as opposed to all that effort with little to show for it. 'It really is an important positive finding for global health,' he said. Murray said no one had approached him directly about delaying the release of his findings; he heard about those efforts from The Lancet, and described them as 'disappointing.' He said, 'We believe in the process of peer-reviewed science, and it's the proper way to pursue these sorts of studies.' The researchers analyzed maternal mortality in 181 countries from 1980 to 2008, using whatever information they could glean from each country: death records, censuses, surveys and published studies. They ultimately gathered about three times as much data as the previous researchers had found. Among poor countries with longstanding high death rates, progress varied considerably. For instance, from 1990 to 2008, the maternal death rate dropped 8.8 percent a year in the Maldives, but rose 5.5 percent in Zimbabwe. Sub-Saharan Africa has the highest maternal death rates. Brazil improved more than Mexico, Egypt more than Turkey. Six countries accounted for more than half of all the maternal deaths in 2008: India, Nigeria, Pakistan, Afghanistan, Ethiopia and the Democratic Republic of Congo. But India has made steady progress, and because its population is so large, its improvements have helped considerably to decrease the worldwide rate of maternal deaths. China has also made considerable progress. In India, there were 408 to 1,080 maternal deaths per 100,000 live births in 1980, and by 2008, there were 154 to 395, the new study found. In China, there were 144 to 187 deaths per 100,000 live births in 1980, and 35 to 46 in 2008. Murray said the findings came as a surprise. What also surprised him and his colleagues, he said, was the number of pregnant women who died from AIDS: about 60,000. 'Really to a large extent that's why maternal mortality is rising in eastern and southern Africa,' Murray said. 'It means, to us, that if you want to tackle maternal mortality in those regions, you need to pay attention to the management of HIV in pregnant women. It's not about emergency obstetrical care, but about access to antiretrovirals.' Horton contended that the new data should encourage politicians to spend more on pregnancy-related health matters. The data dispelled the belief that the statistics had been stuck in one dismal place for decades, he said. So money allocated to women's health is actually accomplishing something, he said, and governments are not throwing good money after bad. An advocate for women's health, Dr. Flavia Bustreo, director of the Partnership for Maternal, Newborn and Child Health, said the improvements described in the new report represented 'hope at last.' She said her organization, affiliated with the World Health Organization, was not one of those that tried to delay release of the findings. She said the report was well done and called The Lancet a 'scrupulously' edited journal. She said the findings made sense and were consistent with other reports from large countries like India, which can drive global figures. 'For 20 years, the safe motherhood movement has been conveying an impression of no progress,' Bustreo said. 'To hear confirmation of improvements is good news. To us, the good news will maintain the interest of investors. If you don't show results, that's the worst position you can be in. The evidence and scientific truths have to be put in the open and discussed.' Her group issued its own report on Tuesday, noting improvements that were saving the lives of women during pregnancy and birth in various countries. For instance, India pays women to get prenatal care and skilled care for delivery. Nepal provides home visits for family planning. Malawi is training nonphysicians to perform emergency cesarean sections. Brazil has set up a health system that provides free primary care and skilled attendance at birth for all. 