Background: Labour is a physiologic procedure in which the products of conceptions (i.e. the fetus, umbilical cord, membrane, and placenta) are barred out of the uterus.
Aim of the work:To find out if a parameter resulting from U-S examinations (the occiput-spine angle (OSA)) had a correlation with the course and labour outcome. Patients and methods: this was a prospective observational study was conducted, consisted of 120 pregnant women attended to Al Azhar university El-Hussine hospital. Results: the mean of Occiput-spine angle in normal vaginal delivery group was 123.49 (± 5.16 SD) with range (116.00-135.00) while the mean of OSA in caesarian section delivery group was 115.55 (± 6.09 SD) with range (105.00-124.00). A highly significant change was found among the study groups regarding Occiput-spine angle. Conclusion: the prenatal sonographic evaluation of the flexion degree of the embryonic head by the OSA in fetus could be used to predict course and outcome of labor.