Prediction of postnatal abnormal umbilical cord coiling by antenatal evaluation in pregnant women: Diagnostic accuracy study; a systematic review.

Abstract

Umbilical cord abnormalities increase neonatal morbidity and mortality. Considering uncertainties about the best time of an antenatal ultrasonography scan to evaluate the umbilical coiling index (UCI), this systematic review was designed to assess the diagnostic accuracy value of antenatal ultrasound assessments to predict abnormal postpartum UCI. All observational, cross-sectional, case-control, cohort, and diagnostic accuracy studies up to March 26, 2022, were searched and assessed according to PRISMA guidelines in Ovid, Cochrane, Scopus, PubMed, Web of Science, Embase, Proquest, Science Direct, and Clinical Key databases, and Google Scholar search engine. The total number of 63 190 documents were retrieved from databases. The duplicates (19 272) were removed, 43 918 articles were screened for relevance, and 56 papers were selected for full-text evaluation, resulting in 14 qualified pieces subjected to the quality CASP tools for each type of study. Finally, six articles were evaluated, extracted, and confirmed. Overall, we had 16 evaluations (11 normal pregnancies, 4 gestational diabetes mellitus, and 1 group at risk for small gestational age), from which 9 and 7 were respectively performed in the second and third trimesters. Most of the evaluations considered both hypocoiling and hypercoiling. The sensitivity, specificity, and area under curves (AUCs) change range between the evaluations were 0.09-0.97, 0.59-0.96, and 0.262-0.84, respectively. Observing any coiling abnormalities in every trimester, both the second and third, is highly sensitive to predicting abnormal postnatal UCI (pUCI). Conclusively, any detected antenatal abnormality is worth attention. Both trimesters' evaluations are essential, and no superiority is seen for any of them. The systematic review revealed statistical and clinical heterogeneity; a meta-analysis was impossible.