The Bed-Rest Hoax
The case against a venerable pregnancy treatment
After just a couple of days on bed rest, the material of your body begins to feel different: softer, heavier, a burden to the bone beneath. The thud of the heart in the chest feels deeper: each beat shifts your frame a little. Even though you haven’t used your back for anything, it aches — and when you twist into a new position the ache swivels along with the muscles, can’t be left behind. You fall asleep throughout the day but can’t sleep through the night, and when you bend a limb at the joint, it’s not the transparent sensation you’re used to — you can feel the muscles tugging, the socket creaking in protest. Your body becomes more present, weaker, and more vulnerable: you are aware of it as though it were an alarm that has not yet gone off but could at any moment.
This summer, I checked myself into a progressive Catholic convent in the Pacific Northwest to observe the effects of five days of bed rest on my body and mind. My plan was to spend all but thirty minutes of each day in a small room with framed Bible verses on the walls, lying on my back or side on a spartan twin-size cot. In the thirty minutes I was allowed out of bed, I would shower, take bathroom breaks, or fetch food from the communal kitchen to bring back and eat in bed. In the final moments before my experiment began, I stretched the inner muscles of my thighs and blinked in the warm sunlight. I tried to take pleasure in feeling ordinary, normal, mobile.
Though five days is a relatively short bed-rest regimen, the first week is when some of the most dramatic changes to the body occur. Deconditioning of the cardiovascular system begins within forty-eight hours. The amount of circulating blood decreases, the heart’s total output drops, and the body uses less and less oxygen. Within five days of immobilization, the arteries narrow and stiffen, and the interior lining of the blood vessels becomes less able to flex and tighten.
Illustrations by Shonagh Rae
The body scales itself down rapidly to meet the reduced physiological demands of its new state and then pauses. Eventually, over weeks, bone density decreases and muscle volume declines. Actin and myosin, the proteins that make up muscle, break down into free-floating nitrogen that is flushed from the body through the kidneys. Simply standing up can cause fainting, since the body is no longer used to pumping blood against the pull of gravity.
Hundreds of thousands of years of evolution have enabled us to walk upright, a task few other mammals can manage — sheep and rabbits often lose consciousness or die when held vertical. But the more time a body spends away from plumb, the greater its difficulty in readapting to normal life. For this reason, bed rest is used as an analogue for space travel in NASA experiments: the effect of weightlessness on human bodies can be simulated on Earth by putting subjects to bed at a six-degree negative incline. Prolonged rest is an extreme physiological challenge, a new environment for the body to navigate.
What I’ve described sounds like a sort of bodily erosion, a slow injury or gentle decay, but it also happens to be one of the most commonly prescribed treatments in the United States for pregnant women at risk of preterm birth. Each year as many as 700,000 pregnant women are prescribed some form of bed rest: from several hours a day to round-the-clock immobilization with breaks only to use the bathroom. For some types of high-risk pregnancy, the mother-to-be is hospitalized and prohibited from getting up to relieve or clean herself, from standing, or even from sitting propped up in bed. Strict bed rest — whether at home or in a hospital — often means that a woman has to forfeit exercise, income, and normal domestic tasks such as caring for her family or maintaining her home.
The practice continues despite a growing body of clinical evidence showing that strict bed rest offers no benefits to the fetus or to the mother. It has not been proved effective in treating gestational hypertension, preeclampsia, a shortened cervix, spontaneous abortion, or impaired fetal growth. The hazards of bed rest, on the other hand, are well substantiated: patients may suffer from bone loss, blood clots, muscle atrophy, weight loss, and psychological malaise. Enrollment in one study, in which women carrying twins were randomly admitted to the hospital for bed rest or assigned outpatient care with no activity restriction, was halted midway because of concerns about a possible detrimental effect to the hospitalized group.
Even so, bed rest remains a routine therapeutic intervention for pregnancy, with up to 95 percent of obstetricians reporting that they’ve prescribed it for their patients. Decades after the treatment fell out of favor for other conditions, pregnancy is the last remaining medical territory to which bed rest can lay claim. It is now the domain of those physi cally incapable of movement — those, for example, who have broken all their limbs — and expectant mothers.