Misoprost as a drug for induction of labour in low dose oral solution as effective as the standard dinoprostone: Study
Induction of labour is defined as iatrogenic stimulation of uterine contractions to accomplish delivery prior to the onset of spontaneous labour aimed at delivery by vaginal route. Induction of labour is indicated when the benefits of induction to either mother or fetus outweigh those of pregnancy continuation. It could be done by pharmacological or mechanical method. Pharmacological methods are mainly using either dinoprostone (prostaglandin E2) or misoprostol (prostaglandin E1 analogue). The use of prostaglandins, in different varieties and forms of administration, has become a common method of labour induction. Pharmacological methods are mainly using either dinoprostone (prostaglandin E2) or misoprostol (prostaglandin E1 analogue).
Dinoprostone, prostaglandin E2, is one the prostaglandins, most commonly used to achieve cervical ripening and induction of labour. It has been approved by the Food and Drug Administration, U.S., for cervical ripening in women at or near term by intracervical administration. The gel needs to be kept refrigerated and brought to room temperature immediately before its use.
Misoprostol, as a drug is approved by FDA for reducing the risk of non-steroidal anti- inflammatory drugs-induced gastric ulcers. It is also used to prevent and treat post partum bleeding. American college of Obstetrics and Gynaecology has recommended misoprostol for cervical ripening for induction of labour and dose should be 25mcg.
Misoprostol is safe, reliable, inexpensive and easily available drug that can be given by various routes for induction of labour. It can be stored at room temperature and is easy to handle. It not only causes cervical ripening but induces uterine contractions as well. Dinoprostone on the other hand only causes cervical ripening. It is expensive, needs storage, and is tedious to handle. Many a times it needs augmentation and repetitive dose.
The objective of this study was to study the efficacy and safety of low dose oral misoprostrol (PGE1) solution and compare it with intracervical dinoprostone (PGE2) gel for induction of labour, in women scheduled for induction.
During the study period 220 antenatal cases were randomly allocated into two groups consisted of 110 cases each group. One group received low dose oral misoprostol solution and other group received intracervical dinoprostone gel for induction of labour. All cases were analyzed and outcomes were evaluated.
Successful induction was obtained in majority of cases in both the groups. However, misoprostol was more effective in inducing labour, improving the bishop score and less need for oxytocin augmentation then dinoprostone. Mean induction delivery rate was less in misoprostol group in both nulliparous and multiparous women. Cases with age less than equal to 30 years had a better induction delivery in misoprostol group. Induction done for the reason of post term pregnancy and pre-mature rupture of membrane had better delivery results in misoprostol group. Similarly, irrespective of period of gestation misoprostol had a significantly lower induction delivery duration.
Labour usually starts as a natural process, but at times it needs to be started artificially. Dinoprostone has been used successfully for years as an agent for induction of labour. However, it is tedious to use, requires refrigeration, is expensive, requires trained staff for proper insertion intracervically. Misoprostol as an agent for induction of labour (IOL) agent has rapidly gained popularity because it is inexpensive, stable at ambient temperatures, and easier to administer in comparison to dinoprostone and oxytocin.
In this study, authors found that misoprostol, as a drug for induction of labour in low dose, and as oral solution is as effective as the standard dinoprostone. It is simple to prepare, easy to administer, does not require trained staff, easily available inexpensive drug that can be stored at room temperature. Does not require titration as well. It can be given in patients with leaking per vaginum or premature rupture of membrane, where vaginal administration of either of the two drugs, vaginal misoprostol or dinoprostone is ineffective. Dinoprostone, is an expensive drug, requires refrigeration and trained staff to instil intracervically. When compared with dinoprostone gel, misoprostol acts as a better cervical ripening agent and requires less need for oxytocin augmentation. Low dose oral misoprostol is more effective than Dinoprostone gel for labour induction without compromising safety. Misoprostol can be used in peripheral health centers for induction of labour, where refrigeration is a problem. When compared in two groups in term of maternal and neonatal outcome showed no statistical significance.
Source: Singh et al. / Indian Journal of Obstetrics and Gynecology Research 2025;12(3):570–575
