The US induction rate has more than doubled over a ten-year period from 9% in 1989 to 18.4 % in 1997. Perinatal scientists still universally agree that 41.5 weeks constitutes a normal term pregnancy. However, new induction agents and efforts to lower cesarean rates have changed practice habits. We examined outcomes of induction and of pregnancies of 41 weeks or more in a rural Tennessee direct-entry midwifery practice where induction was not used routinely and women were allowed to go postdates to 42 weeks. Induction was tried when midwives’ judgement was that the amniotic fluid index was unfavorable, when the baby's size threatened to make vaginal birth difficult, and when labor had not begun within 12 hours of premature rupture of the membranes.
For the cohort of 2075 births that were attended in the practice over its 31-year existence from 1970 to 2001, the induction rate was 5.1%. The induction methods most often used were castor oil (4.9 percent of labors) and sweeping of the membranes (0.5 percent of labors). 27.7 percent of pregnancies lasted 41 weeks or more. The analyses examine the outcomes of the induced labors and of the labors which began at 41 weeks or more. Outcome measures include neonatal and postneonatal morbidity and mortality, incidence of meconium-staining, low five-minute Apgar scores, low birthweight, incidence of postpartum hemorrhage, and route of delivery. The results suggest that it is safe to refrain from routine induction when gestation is less than 42 weeks, in the absence of danger signs.
Learning Objectives: At the conclusion of the session , the participant in this session will be able to: 1. Discuss the results of the study including the population served, transfers to hospital, induction methods, cesarean rates for failed induction and birth outcomes. 2. Articulate the clinical and epidemiologic issues surrounding induction and length of gestation. 3. Discuss the potential implications of the study in relation to the existing literature and common practice.
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
Disclosure not received
Relationship: Not Received.