Advertisement

Fetal fibronectin testing for prevention of preterm birth in singleton pregnancies with threatened preterm labor: a systematic review and metaanalysis of randomized controlled trials

Published:April 28, 2016DOI:https://doi.org/10.1016/j.ajog.2016.04.038

      Objective Data

      Fetal fibronectin is an extracellular matrix glycoprotein that is produced by amniocytes and cytotrophoblasts and has been shown to predict spontaneous preterm birth.

      Study

      The aim of this systematic review and metaanalysis of randomized clinical trials was to evaluate the effect of the use of fetal fibronectin in the prevention of preterm birth in singleton pregnancies with threatened preterm labor.

      Study Appraisal and Synthesis Methods

      The research was conducted with the use of MEDLINE, EMBASE, Web of Sciences, Scopus, ClinicalTrial.gov, OVID, and Cochrane Library as electronic databases from the inception of each database to February 2016. Selection criteria included randomized clinical trials of singleton gestations with threatened preterm labor that were assigned randomly to management based on fetal fibronectin results (ie, intervention group) or not (ie, comparison group). Types of participants included women with singleton gestations at 23 0/7 to 34 6/7 weeks with threatened preterm labor. Studies that included management that was also based on the use of sonographic cervical length were excluded. The primary outcome was preterm birth at <37 weeks of gestation. The summary measures were reported as relative risk or as mean differences with 95% confidence interval.

      Results

      Six trials that included 546 singleton gestations with symptoms of preterm labor were included in the metaanalysis. The overall risk of bias of the included trials was low. Women were eligible for the random assignment in case of symptoms that suggested preterm labor at 23–34 weeks of gestation. During admission, before digital examination, a Dacron swab was rotated in the posterior fornix for 10 seconds to absorb cervicovaginal secretions that were then analyzed for the fetal fibronectin qualitative method, with results reported as either positive or negative. Women who were assigned randomly to the fetal fibronectin group had a similar incidence of preterm birth at <37 weeks of gestation (20.7% vs 29.2%; relative risk, 0.72; 95% confidence interval, 0.52–1.01), at <34 weeks of gestation (8.3% vs 7.9%; relative risk, 1.09; 95% confidence interval, 0.54–2.18), at <32 weeks of gestation (3.3% vs 5.6%; relative risk, 0.64; 95% confidence interval, 0.24–1.74), and at <28 weeks of gestation (1.1% vs 1.7%; relative risk, 0.74; 95% confidence interval, 0.15–3.67) compared with the control group. No differences were found in the number of women who delivered within 7 days (12.8% vs 14.5%; relative risk, 0.76; 95% confidence interval, 0.47–1.21), in the mean of gestational age at delivery (mean difference, 0.20 week; 95% confidence interval, –0.26 to 0.67), in the rate of maternal hospitalization (27.4% vs 26.9%; relative risk, 1.07; 95% confidence interval, 0.80–1.44), in the use of tocolysis (25.3% vs 28.2%; relative risk, 0.97; 95% confidence interval, 0.75–1.24), antenatal steroids (29.2% vs 29.2%; relative risk, 1.05; 95% confidence interval, 0.79–1.39), in the mean time in the triage unit (mean difference, 0.60 hour; 95% confidence interval, –0.03 to 1.23) and in neonatal outcomes that included respiratory distress syndrome (1.3% vs 1.5%; relative risk, 0.91; 95% confidence interval, 0.06–14.06), and admission to the neonatal intensive care unit (19.4% vs 8.1%; relative risk, 2.48; 95% confidence interval, 0.96–6.46). Management based on the fetal fibronectin test required higher hospitalization charges (mean difference, $153; 95% confidence interval, 24.01–281.99).

      Conclusion

      Fetal fibronectin testing in singleton gestations with threatened preterm labor is not associated with the prevention of preterm birth or improvement in perinatal outcome but is associated with higher costs.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to American Journal of Obstetrics & Gynecology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Hamilton B.E.
        • Martin J.A.
        • Osterman M.J.
        • Curtin S.C.
        • Matthews T.J.
        Births: final data for 2014.
        Natl Vital Stat Rep. 2015; 64: 1-64
        • Treyvaud K.
        Parent and family outcomes following very preterm or very low birth weight birth: a review.
        Semin Fetal Neonatal Med. 2014; 19: 131-135
        • Lockwood C.J.
        • Senyei A.E.
        • Dische M.R.
        • et al.
        Fetal fibronectin in cervical and vaginal secretions as a predictor of preterm delivery.
        N Engl J Med. 1991; 325: 669-674
        • Leitch H.
        • Egarter C.
        • Kaider A.
        • et al.
        Cervicovaginal fetal fibronectin as a marker for preterm delivery: a meta-analysis.
        Am J Obstet Gynecol. 1999; 180: 1169-1176
      1. Higgins JPT, Altman DG, Sterne JAC. Cochrane handbook for systematic reviews of interventions, version 5.1.0 (update March 2011). The Cochrane Collaboration, 2011. Available at: www.cochrane-handbook.org. Accessed: December 20, 2015.

        • Moher D.
        • Liberati A.
        • Tetzlaff J.
        • Altman D.G.
        Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement.
        J Clin Epidemiol. 2009; 62: 1006-1012
        • Nguyen T.C.Q.
        • Toy E.C.
        • Baker B.
        The cost-effectiveness of fetal fibronectin testing in suspected preterm labor: randomized trial.
        Obstet Gynecol. 2002; 99: 97S
        • Plaut M.M.
        • Smith W.
        • Kennedy K.
        Fetal fibronectin: the impact of a rapid test on the treatment of women with preterm labor symptoms.
        Am J Obstet Gynecol. 2003; 188: 1588-1593
        • Grobman W.A.
        • Welshman E.E.
        • Calhoun E.A.
        Does fetal fibronectin use in the diagnosis of preterm labor affect physician behavior and health care costs? A randomized trial.
        Am J Obstet Gynecol. 2004; 191: 235-240
        • Lowe M.P.
        • Zimmerman B.
        • Hansen W.
        Prospective randomized controlled trial of fetal fibronectin on preterm labor management in a tertiary care center.
        Am J Obstet Gynecol. 2004; 190: 358-362
        • Dutta D.
        • Norman J.E.
        Pilot study into the efficacy of foetal fibronectin testing in minimizing hospital admissions in women presenting with symptoms of preterm labour: a randomised controlled trial of obstetric and neonatal outcomes.
        Arch Gynecol Obstet. 2011; 284: 559-565
        • Lee G.T.
        • Burwick R.
        • Zork N.
        • Kjos S.
        Does the use of fetal fibronectin in an algorithm for preterm labor reduce triage evaluation times?.
        J Matern Fetal Neonat Med. 2013; 26: 706-709
        • Kurtzman J.
        • Chandiramani M.
        • Briley A.
        • et al.
        Quantitative fetal fibronectin screening in asymptomatic high-risk patients and the spectrum of risk of recurrent preterm delivery.
        Am J Obstet Gynecol. 2009; 200: 263.e1-263.e6
        • Ness A.
        • Visintine J.
        • Ricci E.
        • Berghella V.
        Does knowledge of cervical length and fetal fibronectin affect management of women with threatened preterm labor? A randomized trial.
        Am J Obstet Gynecol. 2007; 197: 426.e1-426.e7
        • Berghella V.
        • Hayes E.
        • Visintine J.
        • Baxter J.K.
        Fetal fibronectin testing for reducing the risk of preterm birth.
        Cochrane Database Syst Rev. 2008; 4: CD006843

      Linked Article

      • Randomized clinical trials are not always the best way to assess diagnostic tests: the case of fetal fibronectin testing
        American Journal of Obstetrics & GynecologyVol. 218Issue 1
        • Preview
          Recently, Berghella and Saccone1 published in this journal a meta-analysis on fetal fibronectin as predictor of preterm birth. In this meta-analysis, the authors concluded that women assigned randomly to the knowledge of fibronectin results did not have reduced preterm birth rates compared to a control group. In addition, both groups had similar rates of hospitalization, and use of tocolytics and steroids. Mean hospital costs were even slightly higher in the fetal fibronectin group. This conclusion was based on 6 randomized clinical trials (RCTs) reporting on 546 women with threatened preterm labor; 13% of the included delivered within 1 week after presentation.
        • Full-Text
        • PDF