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


  • R. Archana Department of Obstetrics and Gynaecology, Siddhivinayak Hospital, Thane, Maharashtra, India
  • Sharda Patra Department of Obstetrics and Gynaecology, Lady Hardinge Medical College, New Delhi, India




Cephalopelvic disproportion, Sacral rhomboid dimensions, Primigravidae, Caesarean section


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 primigravidae

Methods: 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.


World Health Organization. The World Health Report 2005: Making every mother and child count. Geneva: World Health Organization, 2005.

Spert H. Gustav Adolf Michaelis and Michaelis’ Rhomboid. Obstetric and Gynaecologic Milestones Illustrated. New York: Parthenon Publishing Group. 1996:162-5.

Bansal S, Guleria K, Agarwal N. Evaluation of Sacral Rhomboid Dimensions to Predict Contracted Pelvis: A Pilot Study of Indian Primigravidae. J Obstet Gynecol Ind. 2011;61(5):523-7.

Rossiter CE, Chong H. Relations between maternal height, fetal birthweight and cephalopelvic disproportion suggest that young Nigerian primigravidae grow during pregnancy. Int J Obstet Gynaecol. 1985;92:40-8.

Deepika N, Kumar A, Shivagami C. Study of anthropometric measurements to predict contracted pelvis. International J Clin Obstet Gynaecol. 2019;3(1):07-11.

Heevy MA, Shahla KA. Maternal height-neonatal birth weight as a risk factor for Caesarean section due to failure of progress in labour. 2006

Kara F, Yesildaglar N, Uygur D. Maternal Height as a Risk Factor for Caesarean Section. Arch Gynecol Obstet. 2005;271(4):336-7.

8Baird D. Dystocia due to faults in the pelvis. Brit J Obstet Gynaecol. 1985;92: 1235–45.

Benjamin SJ, Daniel AB, Kamath A, Ramkumar V. Anthropometric measurements as predictors of cephalopelvic disproportion. Acta obstetricia et gynecologica Scandinavica. 2012;91(1):122-7.

Helen AB. Anthropometric measures as a predictor of cephalopelvic disproportion. Trop Doct. 1997;27:135-8.

Bruno D, Roger VC, Thierry L. The value of maternal height as risk factor of dystocia: A meta-analysis. Trop Med Int Health. 1996; 1:510-21.

Young TK, Woodmansee B. Factors those are associated with caesarean delivery in a large private practice: the importance of pre-pregnancy body mass index and weight gain. Am J Obstet Gynecol. 2002;187:312-8

Alijahan R, Kordi M, Poorjavad M, Ebrahimzadeh S. Diagnostic accuracy of maternal anthropometric measurements as predictors for dystocia in nulliparous women. Iran J Nurs Midwifery Res. 2014;19(1):11-8.

Rozenholc AT, Ako SN, Leke RJ, Boulvain M. The diagnostic accuracy of external pelvimetry and maternal height to predict dystocia in nulliparous women: a study in Cameroon. Int J Obstet Gynaecol. 2007;114(5):630-5.

Liselele HB, Boulvain M, Tshibangu KC, Meuris S. Maternal height and external pelvimetry to predict cephalopelvic disproportion in nulliparous African women: a cohort study. Int J Obstet Gynaecol. 2000;107(8):947-52.

Wianwiset W. Risk factors of cesarean delivery due to cephalopelvic disproportion in nulliparous women at Sisaket Hospital. Thai J Obstet Gynaecol. 2011;19:158-64.






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