Maternal activity restriction to reduce preterm birth: Time to put this fallacy to bed

Abstract

The idea of restricting physical activity for pregnant women (commonly termed 'bed-rest') dates back more than a century and continues to this day. Activity restriction has been proposed as a therapeutic intervention for numerous obstetric complications, including threatened miscarriage, hypertensive disorders, fetal growth restriction, unselected multifetal pregnancies and following assisted reproduction. 1 However, the condition for which bedrest is most widely prescribed, and for which it has been most thoroughly studied, is the prevention of preterm birth among high-risk women. It has previously been opined that the continued use of activity restriction for women at high-risk for preterm birth is likely fuelled by the 'desperate need for an intervention in these women' and an erroneous 'perception of a lack of harm' among both patients and practitioners. 2 This has certainly been the experience of this author. Anecdotally, I have seen an increase in the number of higher-risk patients-especially those with prior preterm births and mid-trimester losses-demanding bed-rest be prescribed in their current pregnancy. Given this recent trend, one is forced to speculate that this may relate to the increasing number of online forums and chat rooms, in which unscientific and frequently ill-informed opinions are shared between patients. We all want the best for our patients and to maximise the chance of a healthy outcome for mother and baby. As such, let us examine the scientific evidence with regard to activity restriction in pregnancy. EFFICACY OF ACTIVITY RESTRICTION IN REDUCING PRETERM BIRTH In 2014, McCarty-Singleton and Sciscione published a thorough literature review examining the evidence underpinning activity restriction to reduce preterm birth. Their conclusions were unambiguous. They found 'no evidence supporting the efficacy of activity restriction to decrease preterm birth'. 2 More recently, in 2019, Matenchuk et al. published a meta-analysis of randomised trials examining outcomes with maternal bed-rest in both developed and developing regions. 3 Of 14 included studies, maternal and fetal outcomes were similar between women with and without activity restriction. Stratification based on geographic region found that, in developed regions, bed-rest was associated with worse obstetric outcomes, namely an earlier gestational age at delivery and a doubling in the number of 'very premature' births (defined variously as before 32-35 weeks in different studies). 3 Two Cochrane reviews have examined the role of bed-rest in preventing preterm birth. 4,5 A 2015 review of bed-rest in singleton pregnancies included only one trial. This trial demonstrated no differences in outcomes for women with and without bed-rest and is included in the 2019 meta-analysis discussed above. 4 A 2017 Cochrane review examined the role of bed-rest in multiple pregnancies. The analysis included six trials (n = 636 women) and failed to demonstrate any evidence to support (or

Cost‐effectiveness of cervical length screening and progesterone treatment to prevent spontaneous preterm delivery in Sweden

“…This cost was not taken into account in other studies [19][20][21][22][23] . Sick leave (bed-rest) is often prescribed for women judged to be at high risk of spontaneous PTD, but has no proven benefit 56,57 .…”