Since the 1980s, abortion using medications taken by mouth – or
'medical abortion' – has been available in a number of countries. In
many places, the drug misoprostol is added to the treatment regimen to
help terminate the pregnancy more safely. Experts in reproductive
health say medical abortions using only misoprostol are common in many
countries where abortions are not permitted because the drug has other,
legal uses, especially to treat stomach ulcers. But they say it is
impossible to know exactly how many abortions the drug is used in,
because of the difficulty in collecting data in countries where
abortion is illegal. More from Rose Hoban.
Misoprostol has some unpleasant side effects, including nausea and vomiting. So, to reduce side effects, some medical practitioners have found that if a woman places the medication directly into her vagina, where it's absorbed into the bloodstream, these side effects can be reduced.
But research from the University of Michigan suggests that this practice may have a deadly side effect. Several women who administered misoprostol vaginally died of infections from an unusual bacterium. Infectious disease specialist David Aronoff became interested when he heard about their deaths. He had been studying a compound called prostaglandin E2 or PGE2 in his lab.
"Misoprostol is a synthetic version of this compound," Arohoff explains. "And we had found some time ago [that] prostaglandin E2 actually is somewhat of a suppressor of normal immune responses, particularly when its production is exaggerated, or enhanced."
Aronoff wondered if the problem with misoprostol wasn't the drug itself, but how the women used it. So, he tested it on rats to see if the drug enhanced bacterial growth in animals that had uterine infections.
Aronoff found that giving the rats misoprostol by mouth had no adverse effects on the uterine infection.
"But when we gave the misoprostol directly into the reproductive tract, into the uterus, at the time of infection, that the infection was much more severe," Aronoff says. "Then we later went on to show that misoprostol could inhibit some of the immune defense functions of cells that are normally very important in protecting the uterus from infection."
Aronoff says researchers need to do more work to find the best ways of using misoprostol to reduce unpleasant side effects. He says it's still too early to use his research to change global reproductive health policy, but adds, "perhaps this will provide an impetus to enhance surveillance of infectious complications of medication abortion on a global basis."
Aronoff says taking misoprostol by mouth has few complications. Some doctors suggest that letting the pill dissolve under the tongue rather than swallowing it seems to reduce the side effects. Aronoff notes that abortions using misoprostol are a safe alternative to many unsafe practices used around the world that result in tens of thousands of women dying each year.
Aronoff's paper is published in The Journal of Immunology.