IRCT201507022248N17 IRCT 2015-08-19 Vice Chancellor for research of the international branch of Iran University of Medical science Effect of Evening Primrose Oil on cervical ripening and pregnancy outcomes The effect of oral Evening Primrose Oil on cervical ripening and pregnancy outcomes in nulliparous women 2015-07-27 anticipated 80 Complete https://irct.ir/trial/1889 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment, Other design features: People will be allocated randomly in one of two groups primrose capsules and placebo.At first, the names of each of the two groups are written on paper and placed in a separate envelope. The first will be removed one of the envelopes the next person will be in the other group and again, the third will be removed one of the envelopes the next person will be in the other group. In this way people will be located in one of two groups until the completion of the sample size . N/A Ripening of cervix. Intervention 1: Oral Evening primrose capsules, from (40 weeks) to ( 40 +6 weeks) , 2 capsules of1000 mg every 12 hours daily for a week ( Manufacturing by Traditional Medicine Research Center Shahed University). Intervention 2: Placebo capsule containing gelatin, 50 mg, 2 capsules every 12 hours daily for a week ( Manufacturing by Traditional Medicine Research Center Shahed University).