recent attention. The pelvic floor is exposed to direct compres sion from the fetal head and to downward pressure from mater nal expulsive eforts. These forces stretch and distend the pelvic floor, resulting in functional and anatomical alterations in the muscles, nerves, and connective tissues. Accumulating evidence suggests that such efects on the pelvic floor during childbirth can afect urinary or anal continence and pelvic support. hese relationships are discussed in Chapter 30 (p. 568).
Lower extremiy nerve injuy in the mother can follow prolonged second-stage labor. Wong and colleagues (2003) reviewed neurological injury involving the lower extremities in association with labor and delivery. The most common mechanism is external compression of the common fibular (formerly common peroneal) nerve. This is usually caused by inappropriate leg positioning in stirrups, especially during prolonged second-stage labor. hese and other injuries are discussed in Chapter 36 (p. 661). Fortunately, symptoms resolve within 6 months of delivery in most women.
Similar to the mother, the incidence of peripartum fetal sepsis rises with longer labors. Caput succedaneum and molding develop commonly and may be impressive (Fig. 22-16, p. 431) (Buchmann, 2008). Mechanical trauma such as nerve injury, fractures, and cephalohematoma are also more frequent and are discussed further in Chapter 33 (p. 627).
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