Bed Rest in Pregnancy Part II: Risks

Part I of this series covered the evidence for bed rest in pregnancy–or rather, the lack of it.  This post will cover the harms associated with bed rest.

Harms of Bed Rest

Many women have a doctor who recommends best rest, and even if women know the evidence doesn’t support it, they think, “better safe than sorry.”  They may worry that if anything bad happens, they will be to blame for not following doctor’s orders.  But they are actually more likely to harm themselves and their babies by following bed rest instructions than by ignoring them.

There are obvious financial and social risks to extended bed rest (or even short-term bed rest, depending on a woman’s life circumstances)–a woman might have to stop working and she might even lose her job.  A woman might have to hire someone to care for her already-born children or hire household help to do chores .  At the very least, she is likely to have to ask hefty favors of family and friends.

Plus, while lying in bed might be relaxing for a day or so for a busy pregnant woman (or even a non-pregnant woman), it gets boring and uncomfortable fast.  There is only so much time other people want to spend in someone’s bedroom (especially when the person can’t even do any of the fun things often associated with the bed).

But risks go beyond the obvious–there are serious medical consequences to bed rest.  Here are some conclusions regarding bed rest risk from the collection of Medline articles:

The prevalence of thromboembolic events among women for whom extended bed rest is prescribed as part of the treatment of premature labor or preterm premature rupture of membranes is significantly increased with respect to that among gravid women who do not receive this therapy and is substantially higher than previously reported. (Kovacevich, et al)

Women who were on bed rest prior to hospital admission had significantly higher reoxygenation scores upon enrollment (t = -8.6, P<.05). Symptoms of postpartum muscle soreness, deconditioning, and difficulty with mobility were reported. Postpartum assessment and rehabilitation are needed to facilitate recovery and prevent long-term injury. (Maloni and Schneider)

Bed rest treatment is ineffective for improving pregnancy weight gain. Lower infant birth weights across all gestational ages suggest that maternal weight loss during bed rest may be associated with an increased risk of fetal growth restriction. (Maloni, et al)

[Postpartum] symptoms [from a checklist] that continued to be reported at 6 weeks by at least 40% of women were fatigue, mood changes, tenseness, difficulty concentrating, back muscle soreness, dry skin, and headache….Length of maternal bed rest was significantly correlated with the number of symptoms at postpartum weeks 1, 2, 4, 5, and 6.

Judith Maloni, an RN/PhD at Case Western, has an excellent review of bed rest, “Antepartum Bed Rest for Pregnancy Complications” (2010).   In it, she notes the following risks (among others–the whole review is worth reading):

The side effects of bed rest have significant implications for short- and long-term maternal and infant health. A number of the more serious antepartum side effects of bed rest persist into the postpartum period, including muscle atrophy and cardiovascular deconditioning, possible bone loss, the influence of inadequate maternal weight gain on infant birth weight, depressive symptoms, and physiologic and psychosocial symptoms.

A recent ACOG presentation reported on women who were on hospital bed rest:

Very few of the women in our study were in treatment for depression or anxiety before or during their hospital stay. Our study suggests that depression and anxiety are relatively common in hospitalized obstetric patients….Depression in pregnancy is associated with poor birth outcomes…

Emily Oster offers a nice overview of bed rest on Slate (I assume there is a longer discussion in her book, Expecting Better).  She notes,

Usually when we consider a medical treatment with no demonstrated benefits and large demonstrated risks, we conclude that it’s a bad idea. In fact, that’s the strong consensus in the medical literature….And, even more surprising, many doctors seem to know this is a waste of time. A 2009 article that reported on a survey of practicing OBs showed that more than half of them say that bed rest has “no” or “minimal” benefit.  And yet: 90 percent of these doctors reported prescribing bed rest!

Part III of this series discusses the ethics of prescribing bed rest for 20% of pregnant women.

*All emphasis in quotes throughout the post is mine