Background: When diagnosing premature rupture membranes is query, choosing the appropriate management needs
additional confirmatory test. Based on their metabolomics, some biochemical markers have been proposed as diagnostic
aids. A perfect test could be composed of combining more than one marker. Combining markers is not arbitrary as some
combinations could inversely impact the diagnostic accuracy of the test.
Aim: Improving sensitivity and specificity of diagnosis of preterm premature rupture of membranes by combining quantitative
insulin like growth factor binding protein 1 (IGFBP-1) with quantitative βHCG and/or quantitative prolactin in cervicovaginal
fluid.
Materials and Methods: It is a cross sectional study. IGFBP-1, prolactin and β-HCG concentrations in vaginal fluid were
examined in 180 patients with sure membrane state and the diagnostic accuracy of each marker and each combination was
determined. The study was conducted between January 2018 and September 2018 in Ain-Shams University Maternity
Hospital after the approval of the institutional ethics committee. Informed consent has been obtained from the patients
before participation.
Results: The sensitivity, specificity, PPV, and NPV of Prolactin with cutoff point 11 μIU/ml are 84.4, 73.2, 73.8,
and 79.5, respectively, gives accuracy percentage 75.4%. The sensitivity, specificity, PPV, and NPV of ILGFBP-1 with
cutoff point 102 μIU/ml are 88.3, 93.5, 100, and 69.4 respectively gives accuracy percentage 81.5%. The sensitivity,
specificity, PPV, and NPV of Β-HCG with cutoff point 104 mIU/mL are 85.1, 83.9, 96.2, and 72.8 respectively gives
accuracy percentage 79.9%. The sensitivity, specificity, PPV, and NPV of the combination of IGFBP-1 and β-HCG
are 78.4, 100, 100 and 64 respectively gives accuracy percentage 89.7. The sensitivity, specificity, PPV, and NPV of the
combination of IGFBP-1 and prolactin are 78.4, 100, 100 and 68.7, respectively, gives accuracy percentage 84.2. The
sensitivity, specificity, PPV, and NPV of the combination of β-HCG and prolactin are 79.8, 100, 100 and 63.6 respectively
gives accuracy percentage 77.2.
Conclusion:Combining IGFBP-1 and β-HCG is the best diagnostic combination to detect amniotic fluid presence in
vaginal fluid. Combined IGFBP-1 and prolactin offered very little improvement compared to IGFBP-1 alone. Adding
prolactin to β-HCG decreased accuracy than each of the other two markers alone.