Comparing Diagnostic Accuracy of Purple line with Transvers Diagonal of Michaelis Sacral to Predict labor Progress

Background & aim: One of the key aspects of maternal care is observing labor progress. Careful assessment of labor progress could provide mothers to be referred on time and could minimize the maternal and neonatal morbidity. This study aimed to compare diagnostic accuracy of purple line with transverse diagonal of Michaelis sacral rhomboid to predict labor progress in nulliparous and multiparous women who referred to Om-ol-banin Hospital, Mashhad, Iran from April to August 2012. Methods: In this double-blind diagnostic accuracy study, 350 nulliparous and multiparous women with a single pregnancy in vertex presentation and gestational age of 38-42 week who admitted in state hospitals of Mashhad were selected using convenience sampling. The transverse diagonal of the Michaelis sacral rhomboid area was measured in cervical dilatation of ? 3 centimeters. Also labor progress and presence or absence of purple lines between the buttocks in the lateral position in the active phase of labor was controlled hourly. Data were analyzed by SPSS version 16 using Mann-Whitney U and Chi-square test. Results: The mean age of the women was 25.22±5 years. Out of 350 women enrolled, 61. 2% were primigravidas and 38.8% were multigravidas. Presence of the purple line with 68.57% sensitivity, 42.66% specificity, and 80.57% validity was accompanied with normal labor progress. Also transverse diagonal of the Michaelis sacral cut-off point of ? 98.5 millimeter was accompanied with normal labor progress with 86.5% sensitivity, 59.45% specificity and 79.65% validity. Conclusion: Transverse diagonal of the Michaelis sacral is better predictor for observing labor progress in comparison with purple line.