*P < 0.05.
Article first published online: 12 AUG 2005
BJOG: An International Journal of Obstetrics & Gynaecology
Volume 107, Issue 9, pages 1181–1182, September 2000
How to Cite
Wai Ngai, S., Chan, Y. M., Lam, H. and Lao, T. (2000), Authors’ Reply. BJOG: An International Journal of Obstetrics & Gynaecology, 107: 1181–1182. doi: 10.1111/j.1471-0528.2000.tb11131.x
- Issue published online: 12 AUG 2005
- Article first published online: 12 AUG 2005
Thank you for the opportunity to reply to the comments by Jackson and Paterson-Brown. Because of the known difference in labour patterns between multiparous and nulliparous women, we presented the data separately in our report1. In fact, when the multiparous and nulliparous women are analysed together, the total duration of labour was still significantly shorter in the misoprostol group (P= 0.006) (Table 1). A significant difference was seen for both the first (P= 0.002) and second stages of labour (P= 0.004). Although the induction-to-delivery interval was shorter in the misoprostol group, this difference did not reach statistical significance (6.5 h vs. 10.1 h; P > 0.05).
|Misoprostol (n= 40)||Oxytocin (n= 40)||P|
|First stage (h)||4.4 (2.8)||7.9 (5.3)||0.002*|
|Second stage (h)||0.5 (0.3)||0.9 (0.7)||0.004*|
|Third stage (min)||1.9 (3.4)||4.7 (4.8)||0.007|
|Total duration of labour (h)||4.7 (2.6)||8.6 (5.6)||0.001*|
|Induction to delivery interval (h)||6.5 (3.2)||10.1 (5.4)||0.05|
Of the 13 women in the misoprostol group who developed tachysystole, five (38.5%) received only a single dose and the others received two doses. In the current trial of Jackson and Paterson-Brown, a different route (vaginal) was used for administration of the drug which might have contributed to the difference in the incidence of tachysystole. The bioavailablility of vaginally-administered misoprostol is about three times that of oral misoprostol2. It was therefore not surprising that 73% of their women with tachysystole had received only a single dose, compared with 38.5% of the women with tachysystole in our study. We recommend increasing the dosing interval to six-hourly instead of four-hourly as used in our study, not because this could prevent the tachysystole in the 38.5% of women who had only one dose, but to reduce the incidence of tachysystole in the other 61.5% of women who required two doses.
The objective of our study was to examine the pattern of labour and uterine activity, and not to compare the caesarean section rates between the groups; for this outcome a very large sample is required as pointed out by Jackson and Paterson-Brown.