STATISTICAL ANALYSIS
All statistical analyses were performed using SPSS version. Assuming that labour data was log normally distributed, distribution of times for progression from one integer centimetre of dilatation to the next was calculated from the median value. Women were plotted on modified WHO partograph, when they are 4 cm dilated so in both groups, the labour curve starts from 4 cm. An interval-censored regression was used and the regression was carried out in reverse, using 10 cm as the starting point and going backward. For normally distributed data, differences between groups were assessed using Student’s t-test. (P < 0.05 for all comparisons) .