.- A Chilean researcher and his colleagues say the Guttmacher Institute's response to a study on abortion's effects on maternal mortality has spread “erroneous and misleading information.”
Dr. Elard Koch, an epidemiologist at the University of Chile with the Chilean Maternal Mortality Research Initiative, said that his project's study showed restrictive abortion laws did not affect maternal mortality trends.
“In fact, maternal mortality ratios steadily decreased over the last fifty years, mainly associated to an increase in educational level of women and maternal health facilities and regardless of the extent of abortion restrictions in the country,” he said May 25.
He and his fellow researchers with the research initiative said “it is absolutely possible for developing countries to decrease maternal and abortion mortality without requiring any liberal law of abortion.”
Their study, titled “Women's Education Level, Maternal Health Facilities, Abortion Legislation and Maternal Deaths: A Natural Experiment in Chile from 1957 to 2007,” was published May 4 on the peer-reviewed online publication PLoS One.
It prompted a response from the Guttmacher Institute, the former research arm of Planned Parenthood. The Guttmacher Institute in a May 23 advisory claimed that the study was inconclusive because Chile's pre-1989 law was “already highly restrictive.” It claimed the study's reliance on Chile's vital statistics registration system was “a critical methodological weakness.”
Koch and his colleagues produced a point-by-point response that said the Guttmacher Institute's advisory comment produced “major misinformation” in depicting Chile's pre-1989 abortion law as highly restrictive.
“Abortion was legal in Chile from 1931 to 1967, after permission of three physicians or one physician and two witnesses,” the researchers explained. “From 1967 to 1989, abortion was simplified and allowed based on the opinion of two physicians.”
The pre-1989 law allowing abortion for “therapeutic reasons” was “loosely interpreted” in many cases to mean abortion on request. The 1989 abortion ban meant a “major transition from a partially restrictive to a fully restrictive law.”
Koch and his colleagues said that even if the Guttmacher Institute were correct about Chile's abortion law, it would not invalidate their study's main conclusion that abortion restrictions did not affect maternal mortality trends in Chile.
The Chilean Maternal Mortality Research Initiative study assessed the impact of many different factors believed to influence maternal mortality, not only abortion legality. Women's education level, better access to maternal health care facilities and professionals, nutrition programs, and sanitary services access were among the other factors judged.
The study found that women's education level is the main factor in the decrease in Chilean maternal mortality, with each additional year of maternal education corresponding to a decrease in the mortality rate of 29.3 per 100,000 live births.
The Guttmacher Institute contended that the abortion numbers drawn from Chile's vital registration system were more unreliable after the procedure was banned. It said that abortion as a cause of death is often misreported or under-reported in countries where the procedure is illegal. It said data sources such as surveys of women and surveys of health professionals are needed to measure the consequences of “unsafe abortion.”
However, Koch and his fellow researchers said the Chilean registry of vital data is “robust and reliable” and is a resource recognized by the World Health Organization, the United Nations and other international groups.
They said studies based on indirect estimates are at substantial more risk of bias than “studies based on actual data.” Indirect estimates are largely based on opinion surveys whose scientific validity is “unknown.”
The researchers charged that the Guttmacher Institute has long used surveys of women and health professionals “almost to the point of abuse.” Though they have some value for anecdotal purposes, they are too flawed to accurately assess the number of induced abortions.
The researchers said their research was “intensively peer-reviewed by independent scientists.”
They also said that the prestigious British medical journal The Lancet had rejected a peer review of their study.
“This is not surprising,” they said, saying their research “seriously challenges” several reports The Lancet has published over the last decade, mostly based on the Guttmacher Institute's indirect estimates of induced abortions.
On May 18, Koch and his colleagues examined the discrepancies between these methdolodies in estimates of illegal abortion in several Latin American countries.
“Not surprisingly, we found that the methodology developed by scientists from the Guttmacher Institute appears to grossly overestimate the number of possible induced abortions in developing countries,” Koch said.
The Guttcmacher Insittute claimed that 400,400 abortions took place in Colombia in 2008, though Koch and his colleagues' methodology estimated only 21,978 procedures took place that year.
Koch has said that the abortion estimates from the Guttmacher Institute are “beyond what is emperically possible.”