Effect of Intravenous Dexamethasone on Preparing the Cervix and Labor Induction

The use of corticosteroids is one of the methods put forward for the strengthening and speeding up the process of labor. after identification of glucocorticoid receptors in human amnion,the role of corticosteroids in starting the process of labor has been studied in numerous studies. the purpose of this study was to determine the effect of intravenous dexamethasone on preparing the cervix and on labor induction. a randomized,clinical,and double – blind trial was conducted on 172 women divided into a control and an experimental group. the inclusion criteria were that they had to be primparous,in or before the 40th week of pregnancy,and with bishop scores (b.s.s) of 4 or lower. the exclusion criteria were diabetes,preeclampsia,macrosomia,twin pregnancy,rupture of the membrane (rom),breech,and women suffering from background diseases. the b.s.s of the women was measured in charge of the study,and each woman was intravenously injected with eight milligrams of dexamethasone or eight milligrams of distilled water. four hours after the injections,the b.s.s of the participants was measured,and they were put under the conditions of labor induction using oxytocin. information was collected in checklists a and b. the patients were compared with respect to b.s.,the time the induction started,the average interval between the start of induction and the beginning of the active phase of childbirth,and the average length of time between the start of the active phase and the second stage of childbirth. the first and five minutes apgar scores of the two groups of women were compared. the frequencies,the means,and the standard deviations were calculated using the spss – 16 software,and analysis of the results was performed with the student’s t- test and the chi-square test with p<0.05. there were no statistically significant differences between the two groups in terms of their age,period of pregnancy,and b.s. at the start of the study. the average b.s. of women four hours after the injections with dexamethasone was 5.9 ± 1.57,and the corresponding figure for women in the control group was 4.6 ± 1.72. these figures were significantly different at p<0.001. the average interval between labor induction and the start of the active phase in the group injected with dexamethasone was significantly less than that of the control group (2.87±0.93 versus 3.80± 0.93 at p<0.001). the average duration of the active phase of the second stage of childbirth was 3.47±1.10 hours in the experimental group and 3.6 ± 0.99 hours in the control group at p<0.49. these two figures were not significantly different. the apgar scores of the first and fifth minutes after the birth of the children of the two groups of women were not significantly different. it was found that intravenous dexamethasone improves the bishop score of the cervix and thus causes softening of the cervix and reduces the length of time between labor induction and the start of the active phase of childbirth. © 2015 tehran university of medical sciences. all rights reserved.