Obstetrics & Gynaecology Forum Volume 29 | Issue 3 | 2019

O&G Forum 2019; 29: 25 - 28 ORIGINAL Discussion is study, conducted amongst an overweight population, where 79% of women were overweight and mean BMI of 30.5, shows a signi - cant in uence of body weight on the success rate of IOL. Additionally, the higher the BMI, the more doses were required to initiate labour. ere was high failure rate of 39% with the regimen used at the hos- pital, with 65% of those who were successful delivering a er the initial “cycle”, compared to only 38% where the cycle was repeated. e dos- age used di ers from the recommended WHO regimen of 25µg every two hours. 23 Various hospitals also follow their own titrated oral dosage regimen according to parity until labour is induced. 24 In addition, the obstetrician’s experience with misoprostol use may also in uences the dosage regimens. 24 In this study, the number of misoprostol doses used for the in- duction varied from 1 to 8 doses with 2, 4 and 8 doses being most common. Success rate in patients given oral misoprostol for IOL in another study 25 showed that 68% IOL occurred with 1 dose of miso- prostol followed by 53% with 2 doses, 24% with 3 doses and 9% with 4 doses. Interestingly, in our study, the highest success rate of 41.9% was at 4 doses. e di erences between studies may be due to BMI. We found a signi cant di erence in BMI of patients who achieved vaginal delivery compared to those with a CS. In addition, we found a highly signi cant correlation between number of doses of misoprostol and BMI in that the number of doses of misoprostol increased with the increasing BMI. Wing et al., (2002) did not find any such associa- tion. 25 An earlier study found that parity; gestational age and Bishop score at entry were significant for predicting successful induction but not BMI. 25 In another study, results showed that time to delivery increased significantly with increasing BMI. Furthermore, women with higher BMI required more doses of misoprostol, a longer expo- sure duration before delivery therefore was at increased risk of CS. 26 Ruhstaller (2015) and Naila (2017) reported that obesity not only increased CS but also the risk of failed induction. 27, 28 BMI can affect the success and failure of IOL. In our study, 104 women (50.7%) had successful IOL and 101 (49.3%) had failed IOL. There was a gradual increase in failed induction related to BMI. In patients with normal BMI, the failed induction rate was 39.5%, 42.4% in the overweight group and peaked at 58.3% in the obese group. In contrast, Naila (2017) reported that 100% of patients with normal BMI had successful induction and 94% in the high BMI group. 28 Study limitations, Conclusion and Recommendation The main limitation of our study was the retrospective nature and that patient files only had cervical length and dilatation documented instead of a complete Bishop score. Our study confirms that BMI influences IOL success in women. We further recommend that if in- duction of IOL is unsuccessful, the indication and method of induc- tion should then be re-evaluated. Acknowledgements We acknowledge Dr C. Tiloke for the assistance in the manuscript preparations. Author Contributions: J.M.B. and H.M.S conceptualized study, re- sponsible for data analysis, interpretation and manuscript prepara- tions. Funding: None Conflict of Interest: None References 1. Goel K, Gedam JK, Rajput DA, Bhalerao MV. Induction of Labor: A Review. Indian J Clin Pract 2014; 24: 1057-1064. 2. ACOG Committee on Practice Bulletins - Obstetrics. ACOG Practice Bulletin No. 107: Induction of labor. Obstet Gynecol 2009; 114: 386-397. 3. Weeks AD, Navaratnam K, Alfirevic Z. Simplifying oral misoprostol protocols for the induction of labour. Br J Obstet Gynecol 2017; 124: 1642-1645. 4. Mackenzie IZ. Induction of labour at the start of the new millennium. Reproduct 2006; 131: 989-998. 5. Moraes Filho OB, Cecatti JG, Feitosa FEL. Methods for labor induction. Rev Bras Ginecol Obstet 2005; 27: 493-500. 6. Sanchez-Ramos L. Induction of labor. Obstet Gynecol Clin North Am 2005; 32: 181-200. 7. Hofmeyr GJ. Induction of labour with misoprostol. Curr Opin Obstet Gynecol 2001; 13: 577- 581. 8. Hofmeyr GJ, Gulmezoglu AM. Vaginal misoprostol for cervical ripening and labour induction in late pregnancy (Cochrane review). In: The Cochrane Library, Issue 2, 2002. Oxford: Update Software. 9. Boulvain M, Kelly A, Irion O. Intracervical prostaglandins for induction of labour. Cochrane Database Syst Rev 2008; 1: CD006971. 10. Souza ASR, Scavuzzi A, Rodrigues DC, Oliveira RD, Feitosa FE, Amorim MM. Titrated oral solution of misoprostol for labour induction: a pilot study. Rev Bras Ginecol Obstet 2010; 32: 208-213. 11. Kavanagh J, Kelly AJ, Thomas J. Hyaluronidase for cervical ripening and induction of labour. Cochrane Database Syst Rev 2006; 2: CD003097. 12. Stephenson ML, Wing DA. Misoprostol for induction of labor. Semin Perinatol 2015; 39: 459-462. 13. Rezaie M, Farhadifar F, Sadegh SM, Nayebi M. Comparison of vaginal and oral doses of misoprostol for labour induction in post-term pregnancies. J Clin Diagn Res 2016; 10: QC08-QC11. 14. Duro Gómez J, Garrido Oyarzún MF, Rodríguez Marín AB, de la Torre González AJ, Arjona Berral JE, Castelo-Branco C. Vaginal misoprostol and cervical ripening balloon for induction of labor in late-term pregnancies. J Obstet Gynaecol Res 2017; 43: 87-91. 15. Loto OM, Fadahunsi AA, Kolade CO. Safety and efficacy of misoprostol for induction of labour in a semi-urban hospital setting. J Obstet Gynaecol 2004; 24: 638-640. 16. Kreft M, Krähenmann F, Roos M, Kurmanavicius J, Zimmermann R, Ochsenbein-Kölble N. Maternal and neonatal outcome of labour induction at term comparing two regimens of misoprostol. J Perinat Med 2014; 42: 603-609. 17. Morris M, Bolnga JW, Verave O, Aipit J, Rero A, Laman M. Safety and effectiveness of oral misoprostol for induction of labour in a resource- limited setting: a dose escalation study. BMC Pregnancy Childbirth 2017; 17: 298. 18. Caliskan E, Doger E, Cakiroglu Y, Ozkan S, Ozeren S, Corakci A. Does cervical length measurement help to predict the success rate of labor induction using misoprostol at term in women with strictly unfavorable cervix? J Turk Ger Gynecol Assoc 2006; 7: 184-188. 19. Malende B, Moodley J, Kambaran SR. Induction of labour at a regional hospital in KwaZulu-Natal, South Africa. S Afr J Obstet Gynecol 2014; 20: 22-26. 20. Mbele A, Makin JD, Pattison RC. Can outcome of induction of labour with oral misoprostol be predicted? S Afr Med J 2007; 197: 289-292. 21. Martin JA, Hamilton BE, Sutton PD, Ventura SJ, Menacker F, Kirmeyer S, Munson ML, Centers for Disease Control and Prevention National Center for Health Statistics National Vital Statistics System. Births: final data for 2005. Natl Vital Stat Rep 2007; 56: 1-103. 22. WHO Global Survey on Maternal and Perinatal Health. Induction of labour data. World Health Organization: Geneva. 2010. 23. WHO recommendations for Induction of Labour. World Health Organization: Geneva. 2011. 24. Madziyire MG, Mateveke B, Gidiri MF. Beliefs and practices in using misoprostol for induction of labour among obstetricians in Zimbabwe. SAJOG 2017; 23: 24-27. 25. Wing DA, Tran S, Paul RH. Factors affecting the likelihood of successful induction after intravaginal misoprostol application for cervical ripening and labor induction. Am J Obstet Gynecol 2002; 186: 1237-1243. 26. Lassiter JR, Holliday N, Lewis DF, Mulekar M, Abshire J, Brocato B. Induction of labor with an unfavorable cervix: how does BMI affect success? J Matern Fetal Neonatal Med 2016; 29: 3000-3002. 27. Ruhstaller K. Induction of labor in the obese patient. Semin in Perinatol. 2015; 39: 437-440. 28. Naila S. Maternal Outcome in Primigravid Women Induced at Term with Normal Versus High Body Mass Index. Ann Pak Inst Med Sci 2017; 13: 139-143. OBSTETRICS & GYNAECOLOGY FORUM 2019 | ISSUE 3 | 28