| BACKGROUNDLabor induction is the use of medications or other methods to bring on (induce) labor. The main purpose of labor induction is to make fetus leave the infaust uterine enviroment earlier and to minimize the complications of pregnant women. The labor induction for pregnancy at term is the most usual approach to deal with high-risk pregnancy. Its success contigent on the status of cervix at the beginning of the induction. Labor induction in the presence of an unfavorable cervix is associated with a higher incidence of prolonged labor, instrumental delivery and induction failture. So cervical ripening is necessary before labor inductoin. It was reported that almost 50% of pregnant women whose cervixes are unripen before labor induction. Therefore it is significant to investigate the cervical ripeing methods.The methods of ripening cervical include mechanical and pharmic method. The mechanical method may result in infection, premature rupture of membrane, cervical injury and other complications, which is rarely used in the clinical work. Cervical ripening agents include oxytocin, prostanoid, mifepristone, estrogen and diazepam. Among of these agents, prostadandins (PG) is the most common drug to ripen the cervix. The cervix-ripening mechanism of PG is to change the formation of extracellular matrix of cervix which can make it soft. For instance, PG can activate collagenase to melt collagenous fiber. Also PG can inhance the formation of connections among the cells of the smooth muscle of uterus. Finally, the smooth muscle of uterine cervix can be relaxed by PG to enlarge cervix.The prostaglandin E2 derivative dinoprostone is the only pharmacologic agent approved by the Food and Drug Administration for cervical ripening and labor induction. This preparation is expensive, and its cost is further increased because many patients require two or more doses to achieve adequate cervical ripening. Recently, a prostaglandin El analogue, misoprostol, has received increased attention as a highly effective cervical ripening agent. This medication has the advantages of being inexpensive, easy to store, and stable at room temperature. The labor guide of American College of Obstetricians and Gynecologists (ACOG) in 2009 suggested 25ug as the initial does of misoprostol for preinduction cervical ripening.Above all, it is significant to compare the safety, efficacy and economical perspective of misoprostol with dinoprostone in labor inducton of pregnancy at term and investigate the proper model and dose for medication.OBJECTIVES1. Compare the effectiveness of misoprostol with that of dinoprostone in full term pregnancy labor induction. 2. Compare the safety of misoprostol and dinoprostone in full term pregnancy labor induction.METHODSReview the clinic studies published in biologic and medical journals at home and abroad from 1990 to 2009, which is on comparision of the effectiveness and safety of misoprostol and dinoprostone in full term pregnancy labor induction.Choose "randomized controlled trial, continuous dinoprostone, constained-release prostaglandin E2, cervical ripening, labor induction" as the index terms to search for the literatures in the Cochrane Library and PUBMED and searched the conference paper manually. The time range was between the built-up time of the database and November 30th 2009.Two independent reviewers evaluated the titles, abstracts, and methods sections of all identified reports of clinical trials. The studies that seemed to fulfill the inclusion criteria were selected and crosschecked. They would discuss to solve the divergence of views.Jadad scale, the common method for quality assessment in Cochrane systematic reviews, was used to estimate the quality of the included essays. The evaluation items included:â‘ generation of randomsequence;â‘¡randomized concealment;â‘¢blinding method;â‘£leaving and loss to follow-up. The quality of included researches was divided into two groups according to the final score of the Jadad scale. Low-quality researches got 1 to 3 points while high-quality ones got 4 to 7 points. Two reviewers did this assessment independently.Meta-analysis was done on the comparision of the effectiveness and safeness of misoprostol and dinoprostone in full term pregnancy labor induction with the RevMan 4.2 statistical software. Sensitivity analysis includedâ‘ excluding unpublished articles;â‘¡excluding low-quality researches;â‘¢excluding the particular long course of treatment or studies with large sample to valuate their impacts to the results. RevMan 4.2 statistical software used random effect model and fixed random model to analyze the data. And the results was expressed with WMD and SMD. Compare these results respectively to evaluate the sensitivity of the Meta-analysis. Funnel plots were used to estimate the possible publication bias.RESULTS209 articles were found with the search strategy mentioned above.9 articles were included after screening one by one according to the inclusion and exclusion criteria. Among the 9 included articles, all of them are RCT.The results of Meta analysis are below:1. Meta-analysis of the comparision the effectiveness of misoprostol and dinoprostone in full term pregnancy labor induction. Clinical evidence of the misoprostol and dinoprostone used in mature pregnancy available so far indicates the indexes of effectiveness, for example vaginal delivery within 24hr.,the vaginal delivery within 12 hr, cervical ripening after 8hr and Cesarean sections, are not statistically significant. Interval between start and delivery of the dinoprostone group is longer than that of the misoprostol group.2. Meta-analysis of the comparision the safeness of misoprostol and dinoprostone in full term pregnancy labor induction. The indexes of security such as complications of gastrointestinal tract, non-assuring fetal heart rate tracing, uterus abnormal contraction, apgar score<7 at 1 min and apgar score<7 at 5 min are not statistically significant.CONCLUSIONSThe evidence of clinical research showed that the interval between start and delivery of the dinoprostone group is longer than that of the misoprostol group, the effectiveness and safeness of the two grous are basically the same.
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