Objective: To study the effect of different doses and intervals time on induction outcome on the middle pregnancy by misoprostol in vagina. Method: One hundred and fifty pregnant women who were to be executed misoprostol induction were divided into observation group and control group

two group were given misoprostol induction

in observation group the interval time was 4 h

at the doae of 200 μg

during 24 hour the maximum dose reaching 800 μg. In the control group the interval time was 6 h

at the dose of 400 μg and 1 200 μg;the pregnant women labor outcome was observed and compared. Result: The success rate

amount of vaginal bleeding in two groups were not statistically significant; in the observation group the time of uterine contraction

the total production process and the dosage were lower than that in the control group (P<0.05)

the incidence of adverse drug reactions was significantly lowe than that in the control group(P<0.01). Conclusion: Misoprostol at dose of 200 μg and 4 h of interval time is safe effective and suitable for clinical application.