Pilot Randomized Controlled Trial to Evaluate the Impact of Bed Rest on Maternal and Fetal Outcomes in Women with Preterm Premature Rupture of the Membranes

Abstract

Objectives Preterm premature rupture of the membranes (PPROM) is spontaneous rupture of membranes before 37 weeks' gestation before the onset of labor. The standard of care is inpatient management with antibiotics and monitoring. Bed rest has not been shown to be beneficial in the setting of PPROM and has adverse maternal effects. We conducted a pilot randomized clinical trial (RCT) to determine the feasibility of recruitment for an RCT of this nature and obtain estimates of the frequency of maternal and neonatal outcomes.

Study Design Patients who were diagnosed with PPROM < 34 weeks gestational age were randomized to bed rest versus activity in a 1:1 ratio. Subjects in both groups wore pedometers and kept activity logs. Maternal demographic and obstetric data and neonatal outcomes were collected and compared between groups using chi-square and Fisher exact tests. Latency was evaluated with log-rank test and Kaplan–Meier analysis.

Results In this study, 36 women were enrolled and randomized; 1 patient withdrew. Complete data were available for 21 subjects. In univariable analysis, women in the activity group had a nonsignificantly shorter latency time than the bed rest group (median 6.0 vs. 8.5 days). Neonatal outcomes were similar between groups. Using log-rank sum analysis, neonates born to mothers in the activity group were more likely to develop necrotizing enterocolitis (NEC) than in the control group (24 vs. 0%, p = 0.05); this difference was not significant after false discovery rate correction (p = 0.80).

Conclusion This is the first randomized controlled study to evaluate bed rest versus normal activity in the setting of PPROM < 34 weeks. This study demonstrates a nonsignificant increase in latency to delivery on bed rest and possible increase in NEC in the activity group; the mechanism remains unclear. We would recommend a larger RCT to better clarify these findings.

Keywords

activity restriction - bed rest - latency - necrotizing enterocolitis - preterm premature rupture of membranes

• References

• 1 Goldenberg RL, Culhane JF, Iams JD, Romero R. Epidemiology and causes of preterm birth. Lancet 2008; 371 (9606) 75-84
• 2 Mercer BM, Miodovnik M, Thurnau GR , et al; National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Antibiotic therapy for reduction of infant morbidity after preterm premature rupture of the membranes. A randomized controlled trial. JAMA 1997; 278 (12) 989-995
• 3 Kovacevich GJ, Gaich SA, Lavin JP , et al. The prevalence of thromboembolic events among women with extended bed rest prescribed as part of the treatment for premature labor or preterm premature rupture of membranes. Am J Obstet Gynecol 2000; 182 (5) 1089-1092
• 4 Promislow JH, Hertz-Picciotto I, Schramm M, Watt-Morse M, Anderson JJ. Bed rest and other determinants of bone loss during pregnancy. Am J Obstet Gynecol 2004; 191 (4) 1077-1083
• 5 LeBlanc AD, Schneider VS, Evans HJ, Pientok C, Rowe R, Spector E. Regional changes in muscle mass following 17 weeks of bed rest. J Appl Physiol (1985) 1992; 73 (5) 2172-2178
• 6 Bloomfield SA. Changes in musculoskeletal structure and function with prolonged bed rest. Med Sci Sports Exerc 1997; 29 (2) 197-206
• 7 Maloni JA, Park S. Postpartum symptoms after antepartum bed rest. J Obstet Gynecol Neonatal Nurs 2005; 34 (2) 163-171
• 8 Maloni JA, Kane JH, Suen LJ, Wang KK. Dysphoria among high-risk pregnant hospitalized women on bed rest: a longitudinal study. Nurs Res 2002; 51 (2) 92-99
• 9 Dunn LL, Shelton MM. Spiritual well-being, anxiety, and depression in antepartal women on bedrest. Issues Ment Health Nurs 2007; 28 (11) 1235-1246
• 10 May KA. Impact of maternal activity restriction for preterm labor on the expectant father. J Obstet Gynecol Neonatal Nurs 1994; 23 (3) 246-251
• 11 Maloni JA, Ponder MB. Fathers' experience of their partners' antepartum bed rest. Image J Nurs Sch 1997; 29 (2) 183-188
• 12 Hobel CJ, Ross MG, Bemis RL , et al. The West Los Angeles Preterm Birth Prevention Project I. Program impact on high-risk women. Am J Obstet Gynecol 1994; 170 (1 Pt 1) 54-62
• 13 Elliott JP, Miller HS, Coleman S , et al. A randomized multicenter study to determine the efficacy of activity restriction for preterm labor management in patients testing negative for fetal fibronectin. J Perinatol 2005; 25 (10) 626-630
• 14 Sosa CG, Althabe F, Belizán JM, Bergel E. Bed rest in singleton pregnancies for preventing preterm birth. Cochrane Database Syst Rev 2015; 3 (3) CD003581
• 15 Hinh ND, Ladinsky JL. Amniotic fluid index measurements in normal pregnancy after 28 gestational weeks. Int J Gynaecol Obstet 2005; 91 (2) 132-136
• 16 Bigelow C, Stone J. Bed rest in pregnancy. Mt Sinai J Med 2011; 78 (2) 291-302
• 17 Morris JM, Thompson K, Smithey J , et al. The usefulness of ultrasound assessment of amniotic fluid in predicting adverse outcome in prolonged pregnancy: a prospective blinded observational study. BJOG 2003; 110 (11) 989-994
• 18 Lee SE, Romero R, Lee SM, Yoon BH. Amniotic fluid volume in intra-amniotic inflammation with and without culture-proven amniotic fluid infection in preterm premature rupture of membranes. J Perinat Med 2010; 38 (1) 39-44
• 19 Xie A, Zhang W, Chen M , et al. Related factors and adverse neonatal outcomes in women with preterm premature rupture of membranes complicated by histologic chorioamnionitis. Med Sci Monit 2015; 21: 390-395
• 20 Dars S, Malik S, Samreen I, Kazi RA. Maternal morbidity and perinatal outcome in preterm premature rupture of membranes before 37 weeks gestation. Pak J Med Sci 2014; 30 (3) 626-629
• 21 Melamed N, Ben-Haroush A, Pardo J , et al. Expectant management of preterm premature rupture of membranes: is it all about gestational age?. Am J Obstet Gynecol 2011; 204 (1) 48.e1-48.e8
• 22 Weintraub AS, Ferrara L, Deluca L , et al. Antenatal antibiotic exposure in preterm infants with necrotizing enterocolitis. J Perinatol 2012; 32 (9) 705-709