Triple blind study to determine the effect of oral capsules of saffron on the severity and duration of the active phase of labor. The main inclusion criteria: nulliparous , 18-35 years, body mass index 5/19 to 30, gestational age 37-42 weeks, dilatation 3-4 cm cervical, cephalic presentation. Main exclusion criteria: using any herbal drug during the past 48 hours, addiction or using a variety of tobacco and alcohol, the risk of pregnancy complications, or history of any systemic illness or mental disease, the fetus with maternal pelvic disproportion, abnormal fetal heart rate, obstetric complications , cesarean indication, allergic reaction to the saffron
Study Population, all nulliparous women that go to the hospital for delivery. Sample size:60. In the beginning of the study, one capsule (Saffron or placebo which is determined with a code), is given to the subjects for oral consumption. Pain severity was measured each hour until the end of active phase of first stage. Uterine contraction pattern is recorded every 30 minutes using tocodinamometer. Considering to the pattern of uterine contractions, fetal heart rate and the mother's vital signs, drug dose was repeated every 2 hours up to a maximum of three doses. If the dilation was according to the pattern of uterine contractions, the next dose of capsule is not used. If uterine contractions were hypertone , poor progress in labor or need to pain relief by pharmacological methods, appropriate measurement is performed and she is excluded from study