Scientists disagreed Thursday over whether the abortion pill RU-486 played any role in the deaths of four California women who died from a rare bacterial infection.
One researcher said he believes RU-486 enabled the deadly bacteria, and another scientist recommended use of the pill be reduced or eliminated. But other experts at a scientific meeting exploring the cases emphatically challenged those conclusions, calling them at best premature.
"I don't think there's a consensus" among medical experts, said Dr. Sandra Kweder of the U.S. Food and Drug Administration.
The possibility of RU-486 being a cause of death has stirred political interest too, with some anti-abortion groups calling for pill sales to stop.
"Healthy women who have taken these pills have already died, and hundreds more have suffered serious adverse events. What further evidence do we need to tell us this drug is not safe and ought to be pulled from the market?" Randall O'Bannon, director of education and research for National Right to Life, said in a prepared statement issued after the meeting.
The scientists had gathered to explore emerging bacterial infections, including a possible link between RU-486 — also known as Mifeprex or mifepristone — and a bacterium known as Clostridium sordellii.
C. sordellii has been linked to four abortion pill deaths in California and one in Canada since 2000. In each case, the women took RU-486 in combination with another drug, misoprostol.
The abortion pill may suppress the immune system, which would increase susceptibility to bacteria already present in the vaginal canal, said Dr. Ralph Miech an associate professor of pharmacology at Brown University, one of the featured panelists.
Another panelist — Dr. James McGregor, an obstetrics professor at the University of Colorado Health Sciences Center — said the risk of death from medical abortions, 1 in 80,000, is significantly higher than the 1-in-1 million risk from surgical abortions. RU-486 appears to be a contributing to that statistical difference, McGregor said.
"I recommend we reduce or eliminate mifespristone, or at least consider that," McGregor said.
Others at the conference said such a statement was premature. They said that if Miech's hypothesis were correct, why didn't other, more common infections plague the women instead of C. sordellii?
Some raised questions about misoprostol, which causes uterine contractions to help the woman expel the aborted fetus. The contractions help draw bacteria into the uterus, and that may also be a contributing factor, said Kweder, deputy director the FDA Center for Drug Evaluation and Research's Office of New Drugs.
More question marks: The nation has a better system for reporting bacterial infections related to taking pharmaceuticals than it does for bacterial infections in general, and it's possible there are many more C. sordellii infections that have no connection to medical abortions.
One researcher, Dr. Dennis Stevens of the Veteran Affairs Medical Center in Boise, Idaho, presented information on 43 cases of patients with C sordellii, 31 of whom died. About half were women, including five who had pill-induced abortions, but there also were nine who apparently developed the infection after delivering a baby. The male cases included a 4-year-old boy who died after C. sordellii infected his broken arm.
Researchers at the conference focused largely on another bug, Clostridium difficile, also known as C-diff. The colon-dwelling germ is spread by spores in feces, and may cause 500,000 infections or more a year, federal health officials said.
C-diff is becoming a regular menace in hospitals and nursing homes, and was blamed for more than 100 deaths over 18 months at a hospital in Quebec.
Most patients sickened by C-diff took antibiotics first, and researchers believe the medicines suppressed other bacteria and allowed the more harmful C-diff to proliferate.
But C-diff also has been seen in patients who are not in hospitals and not on antibiotics. Late last year, the CDC reported that cases were reported in 33 otherwise healthy people since 2003. Most said they hadn't been to a hospital within three months of their illness, and eight said they hadn't taken any antibiotics in that span.
One of the 33 patients died — a Pennsylvania woman who was 14 weeks pregnant with twins when she first went to the emergency room with symptoms. Researchers say they've been investigating other cases of the bacterial infection in pregnant women.
Researchers said two antibiotics used to treat C-diff have met with mixed success. Other treatments are under development, including vaccines.
The U.S. Centers for Disease Control and Prevention is also investigating cases of C-diff in pigs and cattle that have important similarities to versions found in humans. However, investigators have not yet linked human C-diff illnesses to tainted food, said Dr. L. Clifford McDonald, a CDC epidemiologist.