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Aug. 16, 2000 (Washington) -- Steroids can do much more than help bodybuilders bulk up. When given to women who are in danger of delivering their babies early, for example, they can help keep infants born prematurely from suffering lung injuries, brain hemorrhage, and even death.
But how many doses of steroids should these women get? A panel of experts assembled by the National Institutes of Health (NIH) is being asked to decide. In 1994, the same group of scientists recommended that a single course of treatment -- just two shots -- could significantly reduce lung problems in these developing infants.
Back then, only a handful of women received the injections, but that has since changed dramatically. Most women who are facing premature delivery get steroids at least once, but now many expectant mothers may get the shots every seven days until week 34 of pregnancy, when it's believed the drugs no longer work.
"It's controversial, and [physicians'] ... practices are all over the map," Duane Alexander, MD, director of the National Institute of Child Health and Human Development (NICHD), tells WebMD. Hoping to resolve the debate, a panel of specialists in fetal and maternal health will review the increasing volume of scientific data on the issue on Thursday and Friday at the NIH campus just outside Washington.
The hope is that these scientists will reach a consensus over the best way to use the drugs, but that is by no means guaranteed.
Steroids have been used to help premature infants for some 30 years. But there are two points of view on their use, says Katherine Spong, MD, who heads the maternal-fetal medicine unit network at the NICHD. Some obstetricians/gynecologists give a two-shot course of treatment only if there's an episode of preterm labor. The drug takes up to 48 hours to reach its maximum effectiveness, which lasts about one week.
Other doctors continue to administer the drug every week until the woman delivers, even though there is no guarantee that the extra doses offer a benefit. The logic is that by keeping the drug on board, the baby will be better protected in case the mother again starts to deliver prematurely. "The evidence that's out there only says that [the steroid treatment] works for seven days. After seven days, all bets are off," Spong tells WebMD.
Doctors are worried about the potential downside of steroid use in pregnant women. Some infants exposed to the drugs have smaller heads and delayed development of important motor skills. Apparently, steroids pose little or no risk to the mother.
The existing studies on prenatal steroid use are considered inconclusive, since they focus either on women who received a series of shots but remained pregnant, or on those who received one treatment, then delivered. The groups simply aren't comparable.
Still, new findings will be presented at the meeting. In addition, a major international study is about to begin that will compare women getting more than one dose of steroids with another group receiving a placebo injection after initially getting the steroids. Ultimately, that should resolve the issue, but it could take years, and millions of dollars, to reach an answer.
In the meantime, the NIH consensus process may be able to come up with a recommendation that can reduce the confusion, while saving lives and money.