Commonly prescribed agents include evening primrose oil, black haw, black and blue cohosh, and red raspberry leaves. Given rapid growth in the herbal-supplement industry, it is not surprising that patients request information about alternative agents for labor induction.
Pharmacologic Cervical Ripening or Labor Induction.
Bishop scores of less than 6 usually require that a cervical ripening method be used before other methods. The duration of labor is inversely correlated with the Bishop score a score that exceeds 8 describes the patient most likely to achieve a successful vaginal birth. The Bishop score ( Table 1) 1 helps delineate patients who would be most likely to achieve a successful induction. In 1964, Bishop systematically evaluated a group of multiparous women for elective induction and developed a standardized cervical scoring system.
Various scoring systems for cervical assessment have been introduced. Over the past few years, there has been an increasing awareness that if the cervix is unfavorable, a successful vaginal birth is less likely. 1 Induction of labor refers to the process whereby uterine contractions are initiated by medical or surgical means before the onset of spontaneous labor. The exact mechanisms responsible for this process are currently not well understood. It is a clinical diagnosis defined as the initiation and perpetuation of uterine contractions with the goal of producing progressive cervical effacement and dilation. Labor is a process through which the fetus moves from the intrauterine to the extrauterine environment. When the Bishop score is favorable, the preferred pharmacologic agent is oxytocin. Pharmacologic agents available for cervical ripening and labor induction include prostaglandins, misoprostol, mifepristone, and relaxin. Of these nonpharmacologic methods, only the mechanical and surgical methods have proven efficacy for cervical ripening or induction of labor. Nonpharmacologic approaches to cervical ripening and labor induction have included herbal compounds, castor oil, hot baths, enemas, sexual intercourse, breast stimulation, acupuncture, acupressure, transcutaneous nerve stimulation, and mechanical and surgical modalities. When the Bishop score is less than 6, it is recommended that a cervical ripening agent be used before labor induction. Assessment is accomplished by calculating a Bishop score. Therefore, cervical ripening or preparedness for induction should be assessed before a regimen is selected. In the absence of a ripe or favorable cervix, a successful vaginal birth is less likely. According to the most current studies, the rate varies from 9.5 to 33.7 percent of all pregnancies annually. For multiparous patients, induction at 38 weeks or before is associated with an increased rate of cesarean delivery.Induction of labor is common in obstetric practice.
Obstetricians with induction rates >40% significantly decreased the incidence of delivery after 40 weeks, which lowered their cesarean section rates, but no net lowering occurred because of increased rate of cesarean section <39 weeks.ĬONCLUSION:A fetal weight of 4000 g or more is not an indication for induction of labor. Delivery of multiparous patients before 39 weeks did also. Delivery of nulliparous and multiparous patients after 40 weeks carried an increased risk of cesarean section. RESULTS:No correlation was found between the rate of induction of labor and the rate of cesarean section. In addition, the relative risk of cesarean delivery was calculated for the entire study population. The average cesarean section rate was determined for each group as well as the percentage of each group's deliveries occurring before 39 weeks, at 39, at 40, and after 40 weeks. Four physician populations were identified: a faculty service and three groups of private practitioners with induction rates 20% to 40%, 40% to 60% and >60%. STUDY DESIGN:Data were analyzed from 1432 deliveries with birthweights >4000 g. OBJECTIVE:To determine whether obstetricians with high rates of induction for the indication of fetal macrosomia had higher or lower cesarean section rates.