Randomised placebo-controlled trial of outpatient (at home) cervical ripening with isosorbide mononitrate (IMN) prior to induction of labour - clinical trial with analyses of efficacy and acceptability. The IMOP Study

Bollapragada, S., MacKenzie, F., Norrie, J.D., Eddama, O., Petrou, S., Reid, M. and Norman, J.E. (2009) Randomised placebo-controlled trial of outpatient (at home) cervical ripening with isosorbide mononitrate (IMN) prior to induction of labour - clinical trial with analyses of efficacy and acceptability. The IMOP Study. BJOG: An International Journal of Obstetrics and Gynaecology, 116(9), pp. 1185-1195. (doi: 10.1111/j.1471-0528.2009.02216.x)

Abstract

Objective:  To determine whether isosorbide mononitrate (IMN), self-administered vaginally by women at home, improves the process of induction of labour. Design:  Randomised double blind placebo-controlled trial. Setting:  Large UK maternity hospital. Population or Sample:  Nulliparous women with a singleton pregnancy, cephalic presentation ≥37 weeks gestation, requiring cervical ripening prior to induction of labour. Methods:  IMN (n = 177) or placebo (n = 173) self-administered vaginally at home at 48, 32 and 16 hours prior to the scheduled time of admission for induction. Main outcome measures:  Admission to delivery interval and women’s experience of induction of labour. Results:  IMN did not shorten the admission to delivery interval as compared with placebo [mean difference of −1.6 hours (95% CI −5.1,1.9, P = 0.37)], despite being more effective than placebo in inducing a change in Bishop score [mean difference of 0.65 (95% CI 0.14,1.17, P = 0.013)]. While both groups found the overall experience of home treatment to be positive, (mean score of 3.8/10 ± 2.3/10 for the IMN group, where 1 = extremely good and 10 = not at all good) women in the placebo group found it marginally more positive than those in the IMN group (just over half a unit on a 10-point scale, P = 0.043). There were no differences between the groups in the pain or anxiety experienced or willingness to take the treatment in a subsequent pregnancy. Conclusions:  IMN self-administered vaginally at home does not shorten admission to delivery interval despite a significant effect on cervical ripeness assessed using the Bishop score. However, women report positive views on cervical ripening at home, and the setting deserves further investigation.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Reid, Professor Margaret and Norrie, Prof John and Norman, Professor Jane
• Authors: Bollapragada, S., MacKenzie, F., Norrie, J.D., Eddama, O., Petrou, S., Reid, M., and Norman, J.E.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Robertson Centre; ?? 20206000 ??; College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Journal Name: BJOG: An International Journal of Obstetrics and Gynaecology
• Publisher: Wiley-Blackwell Publishing Ltd.
• ISSN: 1470-0328
• ISSN (Online): 1471-0528