RESULTS
According to inclusion and exclusion criteria, 500 women in labor were recruited and were randomized in 2 groups A (n=250) at 4 cm and group B(n=250) at 6 cm. The baseline variables, including the mean age and mean length of gestation were comparable in both groups. As shown in table 1, the mean duration of labor in progressing from 4-6 cm cervical dilatation and then from 6-10 cm was almost similar in both groups. If total time in reaching from 4-10 cm was observed in both groups, Women in group B took more time to progress from 4 cm to 10cm, but the difference was not statistically significant (P=0.63). The 95th percentile value was 8.27 hours and 9 hours respectively in group A and group B.
Figure 1 depicts labour pattern curves based on median values for both the groups. Assuming that labor data were log normally distributed, distribution of times for progression from one integer centimetre of dilatation to the next was calculated from the median value. Because women were plotted on the modified WHO partograph when they are 4 cm dilated so labor curve starts from 4 cm. Both curve shows that labour accelerates after 6cm cervical dilatation in both groups.
When active phase slope was calculated linearly, the mean slope was found to be 1.1 cm/hour and 1.4 cm/hour in group A and B with no statistical difference. The minimum slope was same i.e. 0.6 cm/hour in both the groups. When comparing slope from 6-10 cm it was 1.6cm/hour and 1.4 cm/hour in groups A and B.
In Table 2, when monitoring was observed using modified WHO partograph, in group A 133 women (53.2%) and in group B, 209 women (83.6%) remained on or left of the alert line which is statistically significant (p=0.0001). In groups A and B 12% and 6.4% crossed the action line respectively.