Publication:

Diagnostic accuracy of sacral rhomboid dimensions in prediction of cephalopelvic disproportion in primigravidae

Background Cephalopelvic disproportion (CPD) is associated with significant maternal and fetal morbidity and mortality in developing countries. CPD complicates 2-15% of pregnancies. This study aimed to determine the diagnostic accuracy of sacral rhomboid dimensions in the prediction of CPD in primigravidaeMethods: This prospective study was conducted on 400 primigravidae at 37-week gestation in Department of Obstetrics and Gynaecology at Lady Hardinge Medical College, New Delhi. Women with height>145 cm were subjected to measurement of transverse and vertical diagonals (TD and VD) of sacral rhomboid prior to delivery. Following delivery, the women were divided in two groups: control group (normal delivery, n=290) and study group (caesarean section for CPD, n=56). The sacral rhomboid dimensions were compared in both the groups and statistically analysed.

Results The mean maternal height in both the groups showed no significant difference (156.88±5.7 vs 155.02±4.75, p=0.011). However, in univariate analysis, maternal height of≤154.5 cm, VD ≤10.25 cm and TD≤9.75 cm showed a diagnostic accuracy of 58.3%, 55.4% and 78%, respectively. Of all the parameters, TD≤9.75 cm was the most significant factor in predicting CPD (34% vs 13%), OR 3.3 (95%CI: 1.7- 6.7, p<0.001).

Conclusions A simple measurement of transverse diameter of sacral rhomboid is a better predictor of CPD in an average height Indian primigravidae. It can be used in community hospital to detect high risk primigravidae.