Risk factors for arrest of descent during the second stage of labor Academic Article uri icon

abstract

  • Arrest of descent in the second stage of labor is a major factor in the rise in cesarean delivery rates over the past 3 decades. The investigators studied the epidemiology of arrested labor in 93,266 deliveries, all singleton, vertex deliveries at turn with no uterine scarring. In 1545 cases, 1.7% of the total, descent was arrested in the second stage of labor. The second stage was limited to 2 hours in nulliparous women (or 3 hours if epidural analgesia was given) and to 1 hour for multiparas (or 2 hours with epidural analgesia). Arrest of descent in the second stage of labor correlated closely with low maternal age, low birth order, fetal macrosomia, and a gestational age of 42 weeks or longer. Pregnancy-induced hypertension and chronic hypertension were more frequent in women with arrested descent, as was gestational diabetes. These women also had higher rates of hydramnios and premature rupture of membranes. At the same time, women with arrested descent had lower rates than did women in the comparison group of oligohydramnios, habitual abortion, and past perinatal death. Any form of induced labor as well as epidural analgesia were risk factors for arrest of descent. Two thirds of the study group were delivered instrumentally or surgically. The odds ratio for surgical delivery was 10.6. Uterine rupture and cervical lacerations both were more frequent than in the comparison group. Women with arrested descent were at increased risk of postpartum bleeding, low hemoglobin, and the need for packed cell infusions. There was no difference in infant mortality despite lower Apgar scores in the study group. On multiple logistic regression analysis, independent risk factors for arrest of descent in the second stage included nulliparity, birth weight exceeding 4 kg, epidural analgesia, hydramnios, hypertension (both chronic and pregnancy-induced), gestational diabetes, male infant, premature rupture of membranes, and induced labor. The odds ratio for arrested descent in a nulliparous woman whose infant weighed more than 4 kg and whose labor was induced was 11.7, and adding diabetes increased it to 18.3.

publication date

  • January 1, 2002