For much of his 20-year career as a maternal-fetal medicine specialist, Anthony J. Sciscione has been criticizing something obstetricians routinely prescribe to try to prevent premature birth: bed rest.
Studies consistently show that pregnant women who lay around for hours at a time, day after day, are just as likely to deliver too early as women who carry on with their normal activities.
Now, Sciscione and like-minded iconoclasts are hammering the mounting evidence that activity restriction during pregnancy is not just unhelpful, but harmful.
Last year, for example, University of North Carolina obstetrician-gynecologist Christina McCall published a paper that concluded bed rest is "unethical."
"Since then, it's gotten a lot of notoriety," said Sciscione, who directs maternal-fetal medicine at Christiana Care Health System in Wilmington, Del.
The latest sign of a shift came last month, when the Society for Maternal-Fetal Medicine issued a new guideline and patient handout written with Sciscione's help.
Citing the many ways that immobility is physically, mentally, and economically risky, the society for obstetricians who specialize in high-risk births recommended "against the routine use of activity restriction or bed rest during pregnancy for any" therapeutic purpose.
Each year, research suggests, about 18 percent of pregnant women in the U.S. are placed on bed rest - although the definition ranges from resting for an hour several times a day to uninterrupted confinement except for bathroom breaks.
This does not mean that specialists have faith in bed rest. A 2009 survey found that while 71 percent would prescribe it for women in preterm labor and 87 percent for premature rupture of membranes (the woman's "water breaks"), most said they expected little or no benefit.
And in 2012, when the American College of Obstetricians and Gynecologists issued the only other U.S. guidelines, it said bed rest should not be routinely used because it hasn't been shown to work.
So why do doctors persist in prescribing it?
Mostly because they have little else to offer. Despite all the advances in medicine, the underlying causes of preterm labor and delivery remain mysterious. The only thing proven to reduce the chance of preterm birth is supplementation with the hormone progesterone.
"When no treatment exists, a common response of clinicians is to 'do something,'" McCall wrote last year in the journal Obstetrics & Gynecology. "Unnecessary interventions such as bed rest may make the patients (and sometimes the health-care provider) feel that all attempts are being made to 'save' the pregnancy."
The problem is that prolonged inactivity is not benign. The new guidelines, and an article reviewing the medical literature that Sciscione published, cite the growing list of documented dangers:
n Lack of weight-bearing activity results in loss of muscle mass, bone mass, blood plasma volume, and cardiovascular conditioning. Measurable harm can occur after only a few days. After giving birth, one study found, 71 percent of women had trouble with stairs, and 14 percent needed help walking.
n Despite burning up fewer calories, restricted women typically lose weight, probably because of muscle loss. Their babies also have lower birth weights compared with unrestricted women.
n Higher rates of gestational diabetes and life-threatening blood clots in the lungs and legs are linked to bed rest.
n Depression and anxiety are far more common when stuck in bed. Women who have to take prolonged leaves from work worry about lost income and possible job loss.
The emotional toll on the rest of the family "is also high," Sciscione says. One study found children were frightened or confused about the health of their mothers and unborn siblings.
While Sciscione hopes that professionals are finally waking up to these harms, the lay public is another matter. Last week, he did an online search and found a dozen books on bed rest during pregnancy, most by women who fervently believed it was good for their babies.
"This is so inbred and ingrained," he said.