Effect of oestrogens on myometrial contractions. Cervical ripening before medical induction of labor: a comparison of prostaglandin E2, estradiol, and oxytocin. Comparative study of oestradiol and prostaglandin E2 vaginal gel for ripening the unfavourable cervix before induction of labour. Outpatient cervical ripening with prostaglandin E2 and estradiol. A randomized controlled trial of extra-amniotic ethinyloestradiol for cervical ripening in multiparas.
nan Our purpose was to evaluate the effectiveness of oxytocin, prostaglandin E2 intracervical gel, and estradiol cream for ripening the very unfavorable cervix in patients requiring induction of labor at term.
                This prospective, randomized study was conducted in a population of women with a very unfavorable cervix (Bishop score < 4) requiring induction of labor. The patients received prostaglandin E2 gel (0.5 mg) intracervically (three doses 6 hours apart), 4 mg estradiol cream in the anterior fornix of the vagina (three doses 6 hours apart), or oxytocin at induction per protocol with an infusion pump.
                Ninety-nine women were recruited into this trial and evenly distributed among the three groups. The demographics of maternal age, race, parity, gestational age, initial Bishop score, and indication for induction were similar among the groups. The incidence of cesarean deliveries was similar in the three groups with approximately 59% of pregnancies delivered abdominally. For patients undergoing abdominal delivery the maximum cervical dilatation among the oxytocin, estradiol, and prostaglandin E2 groups was similar (3.90 +/- 3.02 cm, 3.63 +/- 2.79 cm, and 4.65 +/- 2.78 cm, respectively; p > 0.05). For all patients birth weight and Apgar scores at 1 and 5 minutes were comparable across all regimens (p > 0.05). In the subset of patients delivered vaginally patients receiving oxytocin for cervical ripening had the greatest improvement in Bishop score over baseline (p = 0.023) with an improvement of 7.08 +/- 2.42.
                No differences were detected among prostaglandin E2 gel, estrogen, and oxytocin in relation to cervical ripening in patients with an unfavorable cervix at term who require an induction of labor. Patients with a very unfavorable cervix at term who require delivery may benefit from serial ripening and inductions. Oestradiol 150 mg and prostaglandin E2 (PGE2) 4 mg suspended in viscous gel and applied intravaginally were compared with regard to ripening the unfavourable cervix of patients randomly allocated to two study groups. In primigravidae no significant difference was observed in the efficacy of the two substances. Some multiparous patients, however, had considerably more uterine sensitivity to PGE2 quickly developed decelerative cardiotocographic tracings after insertion of the gel. In the group given oestradiol there was a significant absence of uterine activity after gel application. The findings suggest that oestradiol applied vaginally is a safe, comfortable, cheap, and equally effective alternative to PGE2 for ripening the cervix, without the disadvantages of uterine stimulation frequently encountered with PGE2. To determine whether weekly outpatient administration of prostaglandin gel or estrogen cream initiated labor in women with an unfavorable cervix.
                All uncomplicated pregnancies at term gestation who were candidates for a vaginal delivery with a Bishop score of < or = 6 were randomly assigned to receive on a weekly basis: prostaglandin E2 gel (n = 41); estrogen cream (n = 44); or inert lubricant jelly (n = 43).
                In the three groups no differences were observed among 128 subjects in the weekly Bishop scores, cervical dilatation or gestational age upon admission to the labor and delivery suite, the percentage of patients presenting with spontaneous labor or ruptured membranes, the number of post-date inductions or neonatal outcome.
                Weekly out-patient cervical ripening using either prostaglandin gel or estrogen in women with an unfavorable cervix at 37 weeks' gestation was no more effective than a placebo in Bishop score improvement or in preventing post-date inductions. A double-blind randomized controlled trial was carried out to determine if ethinyloestradiol applied extra-amniotically would ripen the unfavourable cervix at term. Twenty five multiparas were given 150 mg ethinyloestradiol gel while 25 multiparas were given gel alone. There was no difference between the ethinyloestradiol and control groups in either mean change of Bishop score or the induction-to-delivery interval.
There were insufficient data to quantify the safety and effectiveness of oestrogen as an induction agent; they should only be used as part of randomised control trials as there are alternative effective options for inducting labour.