Association and prediction of amniotic fluid measurements for adverse pregnancy outcome: systematic review and meta‐analysis. (7th February 2014)

• Record Type: Journal Article
• Authors: Morris, RK; Meller, CH; Tamblyn, J; Malin, GM; Riley, RD; Kilby, MD; Robson, SC; Khan, KS
• Is Part Of: BJOG. Volume 121:Number 6(2014:Jun.)
• Page Start: 686
• Page End: 699
• Publication Date: 2014-02-07
• Subjects: Obstetrics -- Periodicals; Gynecology -- Periodicals; 618
• DOI: 10.1111/1471-0528.12589
• Languages: English
• ISSNs: 1470-0328

Abstract

<abstract abstract-type="main" id="bjo12589-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="bjo12589-sec-0001" sec-type="section"> <title>Background</title> <p>Measurements of amniotic fluid volume are used for pregnancy surveillance despite a lack of evidence for their predictive ability.</p> </sec> <sec id="bjo12589-sec-0002" sec-type="section"> <title>Objective</title> <p>To evaluate the association and predictive value of ultrasound measurements of amniotic fluid volume for adverse pregnancy outcome.</p> </sec> <sec id="bjo12589-sec-0003" sec-type="section"> <title>Search strategy</title> <p>Electronic databases (inception to October 2011), reference lists, hand searching of journals, contact with experts.</p> </sec> <sec id="bjo12589-sec-0004" sec-type="section"> <title>Selection criteria</title> <p>Studies comparing measurements of amniotic fluid volume with adverse outcome, excluding pre‐labour ruptured membranes or congenital/structural anomalies.</p> </sec> <sec id="bjo12589-sec-0005" sec-type="section"> <title>Data collection</title> <p>Data on study characteristics, design, quality. Random effects meta‐analysis to estimate summary odds ratios (prognostic association) and summary sensitivity, specificity and likelihood ratios (predictive ability).</p> </sec> <sec id="bjo12589-sec-0006" sec-type="section"> <title>Main results</title> <p>Forty‐three studies (244 493 fetuses) were included demonstrating a strong association between oligohydramnios (varying definitions) and birthweight <10th centile (summary odds ratio [OR] 6.31, 95% confidence interval [95% CI] 4.15–9.58; high‐risk population [author definition] <italic>n</italic> = 6 studies, 28 510 fetuses), and mortality (neonatal death any population summary OR 8.72, 95% CI 2.43–31.26; <italic>n</italic> = 6 studies, 55 735 fetuses; and perinatal mortality high‐risk population summary OR 11.54, 95% CI 4.05–32.9; <italic>n</italic> = 2 studies, 27 891 fetuses). There was a strong association between polyhydramnios (maximum pool depth >8 cm or amniotic fluid index ≥25 cm) and birthweight >90th centile (OR 11.41, 95% CI 7.09–18.36; <italic>n</italic> = 1 study, 3960 fetuses). Despite strong associations, predictive accuracy for perinatal outcome was poor.</p> </sec> <sec id="bjo12589-sec-0007" sec-type="section"> <title>Author's conclusion</title> <p>Current evidence suggests that oligohydramnios is strongly associated with being small for gestational age and mortality, and polyhydramnios with birthweight >90th centile. Despite strong associations with poor outcome, they do not accurately predict outcome risk for individuals.</p> </sec> </abstract>