Oral and vaginal route of misoprostol for induction of labour: a comparative study
DOI:
https://doi.org/10.18203/2320-1770.ijrcog20191950Keywords:
Induction of labour, Misoprostol, Oral route, Vaginal routeAbstract
Background: Induction of labour can be defined as “Artificial initiation of uterine contractions before the onset of spontaneous labour, after the period of viability, by any methods, for purpose of vaginal delivery.” The key factor for a successful induction is the status of cervix, its form, consistency and dilatation which is determined by the Bishop score. In case of unfavourable cervix or in the pregnancies remote from the term; prostaglandins are more effective than any other method of induction. Introduction of misoprostol, PGE1 analogue, for the induction of labour in 1993 and its approval for clinical use by ACOG (American College of Obstetrics and Gynecology) in 1999 has been the most significant advancement. It is the latest drug for induction of labour which is cheap and stable at room temperature and is being used worldwide in different doses and by various routes. We compared the most commonly preferred two routes; vaginal and oral in terms of success of induction and noted the adverse events and side effects in both routes.
Methods: This was a prospective comparative study carried out at SBKSMIRC (Shrimati Bhikhiben Kanjibhai Shah Medical Institute and Research Centre), Dhiraj general hospital, Vadodara, Gujarat, 200 patients who required induction of labour were recruited after applying inclusion and exclusion criteria and were randomly divided in two groups- Group A meant to receive 50µg oral misoprostol, Group B - meant to receive 25µg vaginal misoprostol repeated 4 hourly up to maximum of five doses. Progress of labour was charted on the partograph. The mean induction delivery interval, mode of delivery, maternal and neonatal outcomes and complications were observed.
Results: The mean induction to delivery interval was significantly less in vaginal group than oral (23.3±12.4 hours in oral vs. 17.3±10 hours in vaginal). Vaginal delivery and cesarean section rates were comparable in both groups (76% in Group A vs. 72% in Group B for vaginal delivery, 18% vs. 20% for Cesarean section, respectively). 58% patients in Group A required more than two doses as compared to 39% in group B, though the difference was statistically not significant. Significant number of patients required added oxytocin administration in Group A (72%). No major complications or adverse events were observed. Neonatal hyperbilirubinemia was seen more in Group A.
Conclusions: Both Oral misoprostol in a dose of 50μg and vaginal misoprostol 25 μg every four hours, to a maximum of five doses, have the potential to induce labour safely and effectively. The vaginal route however is beneficial in effecting delivery in lesser time with few numbers of doses as compared to oral route.
References
National Institute of Clinical Excellence (NICE) clinical guideline 70. Induction of labour. London: NICE. 2008.
Rayburn COF. Pre induction cervical ripening. Basis and methods of current practice. ObstetGynaecol Survey. 2002;67:683-92.
Sanchez Ramos L, Kuntiz AM, Wears RL, Misoprostol for cervical ripening and labour induction: A Meta analysis. Obstet Gynaecol. 1997;89:633-42.
Ramsey PS, Ogburn Pl, Jr. Harris DY, Heise RH, Ramin KD. Effect of vaginal PH on efficacy of misoprostol for cervical ripening and labour induction. Am J Obstet Gynaecol. 2000;182(6):1616-9.
Cheng S, Ming H, Lee J. Titrated oral compared with vaginal misoprostol for labour induction: a randomized controlled trial. Obstet Gynaecol. 2008;111:119-25.
Carlan SJ, Bouldin S, Biust Danielle O, Brien WF; safety and efficacy of misoprostol for labour induction. A randomized controlled trial. Obstet Gynaecol. 2001:98:107-12.
Pollnovv DM., BroeKhuizen FF. Randomized double blind trial of prostaglandin E2 intravaginal gel versus low dose oxytocin for cervical ripening before induction of labour. Am J Obstet Gynaecol. 1996;174:1910-16.
Off-label drug use and FDA review of supplemental drug applications: hearing before the subcommittee on Human Resources and intergovernmental relations of the committee on government reform and oversight, House of Representatives, 104th Congress, 2nd session, September 12. Washington: USGPO. 1996;53-94.
American College of Obstetricians and Gynecologists. New U.S. Food and Drug Administration labeling on Cytotec (misoprostol) use and pregnancy. ACOG Committee Opinion. Number 283, May 2003. Obstet Gynecol. 2003;101(5 Pt 1):1049-50.
ACOG practice bulletin: Clinical management guidelines for obstetricians and gynecologists. 2009:107.
Alfirevic Z, Keeney E., Dowswell T.,Welton NJ., Dias S., Jones LV. et al. Labour induction with prostaglandins, a systemic review and network meta analysis; BMJ. 2015:350;217-350.
Wing DA, Paul RH. A comparison of differing dosing regimens of vaginally administered misoprostol for preinduction cervical ripening and labour induction. Am J Obstet Gynaecol. 1996;175:158-64. [Erratum in Am J Obstet Gynaecol 1997;176:1423].
Kramer RL, Gilson GJ, Morrison DS, Martin D, Gonzales JL, Qualls CR. A randomized trial of misoprostol and oxytocin for induction of labour: safety and efficacy. Obstet Gynaecol. 1997;89:387-91.
Wing DA, Paul RH. Misoprostol for cervical ripening and labour induction: the clinician’s perspective and guide to success. Contemp Ob Gyn. 1999;44:46-61.
Hofmeyr GJ. Misoprostol administered vaginally for cervical ripening and labour induction in the third trimester [Cochrane Review on CD-ROM]. Oxford, England: Cochrane Library Update Software. 1998;3.
Alfirevic Z, Weeks A. Oral misoprostol for induction of labour. Cochrane Database Syst Rev. 2006:2:Art.CD001338.
Nagai SW, To WK, Lao T, Ho PC. Cervical priming with oral misoprostol in pre-labour rupture of membranes at term. Obstet Gynaecol. 1996;87:923-6.
Windrim R, Bennett K, Mundle W, Young DC. Oral administration of misoprostol for labour induction: a randomized controlled trial. Obstet Gynaecol. 1997;89:392-7.
Curtis P, Evans S, Resnick J. Uterine hyper stimulation: the need for standard terminology. J Reprod Med. 1987;32:91-5.
Janice S. Kwon, Gregory AL. Paul Mackenzie A comparison of oral and vaginal misoprostol for induction of labour at term: a randomised trial. Br J Obstet Gynaecol. 2001;108:23-6.
Rehman H, Pradhar A, Kharka L, Renjhen P, Kar S, Dutta S. Comparative evaluation of 50 microgram oral and 25 microgram intravaginal misoprostol for induction of labour at term: a randomized trial. J Obstet Gynaecol. 2013;35(5):408-16.
Fletcher HM, Mitchell S, Simeon D, Freidrick J, Brown D. Misoprostol for labour induction at term. Br J Obstet Gynaecol. 1993;100;641-4.
Shetty A, Danielian P, Templeton A. A comparison of oral and vaginal misoprostol tablets in induction of labour at term. BJOG. 2001;108(3):238-43.
Jindal P, Avasthi K, Kaur M. A comparison of vaginal vs. oral Misoprostol for induction of labour- Double Blind Randomized Trial. J Obstet Gynaecol Ind. 2011;61(5):538-42.
Drug Review. Misoprostol an old drug, new indications. Br J Postgrad Med. 2002;48(4):336-9.
How HY, Leasebevrge L, Khoury JC. A comparison of various routes and dosages of misoprostol for cervical ripening and the induction of labour. Am J Obstet Gynaecol. 2001;185.
Latika S, Biswajit C. Comparison of prostaglandin E1 (misoprostol) with prostaglandin E2 (dinoprostone) for labour induction. J Obstet Gynecol. 2004;54:139-42.
Evert K, Powers B, Robertson S. Controlled release misoprostol vaginal insert in parous women for labour induction. Obstet Gynaecol. 2006;108:1130-7.
Rasheed R, Alam AA, Younus S, Raza F, Oral vs. vaginal misoprostol for labour induction. J Pak Med Assoc. 2007;57(8):404-7.
WHO recommendations for induction of labour, 2011, Included in the WHO Model List of Essential Medicines, If only 200μg tablets are available, smaller doses can be made by dissolving in water Available at: www.misoprostol.org.