Symphysis-fundal height to identify large-for-gestational-age and macrosomia: a meta-analysis

Bivariate diagnostic meta-analysis was performed to evaluate the diagnostic value of symphysis-fundal height (SFH) for identifying large-for-gestational- age (LGA) (i.e. birth weight >90th centile according to gestational age) and macrosomia (i.e. birth weight >4000 g). Ten databases, e.g. PubMed (MEDLINE), were searched to include English-language studies providing true- and false-positive and true- and false-negative results for this identification. Study quality was assessed using the revised Quality Assessment of Diagnostic Accuracy Studies tool. Synthetic evidence from good quality studies suggested that SFH to identify LGA and macrosomia (n = 23 and 3, respectively) provided a low sensitivity (0.76 and 0.30, respectively), specificity (0.67 and 0.80, respectively) and diagnostic odds ratio (6 and 4, respectively) and 'neither exclusion nor confirmation' strategy (positive and negative likelihood ratios <10 and >0.1, respectively). In conclusion, there is no evidence that SFH is useful to identify LGA or macrosomia.Impact StatementWhat is already known on this subject? Synthetic evidence has shown that symphysis-fundal height (SFH) is not useful for the detection of low birth weight and small-for-gestational-age babies mainly in developing countries. In the present study bivariate diagnostic meta-analysis was carried out to evaluate the diagnostic value of SFH for identifying large-for-gestational age (LGA) and macrosomia.What the results of this study add? SFH to identify LGA and macrosomia provided a low sensitivity (0.76 and 0.30, respectively), specificity (0.67 and 0.80, respectively) and diagnostic odds ratio (6 and 4, respectively) and 'neither exclusion nor confirmation' strategy (positive and negative likelihood ratios <10 and >0.1, respectively).What the implications are of these findings for clinical practice and/or further research?There is no evidence that SFH is useful to identify LGA or macrosomia. Further studies are required to provide more generalisable findings to evaluate the identification of LGA or macrosomia and whether the results can be extrapolated toward the subpopulations that subgroup analysis did not evaluate in this meta-analysis.