Multifetal gestations exhibit certain complications also encountered
during a singleton gestation. Of these, the single most significant
is preterm delivery (see Table 46-1). Once
delivered, the preterm product of a multifetal gestation is at risk
of experiencing any or all known complications of prematurity, including
respiratory distress syndrome, intraventricular hemorrhage, necrotizing
enterocolitis, growth failure, and developmental delay. Prior to
delivery, multiples are more likely to have delayed growth, especially
during the third trimester. Breech or other abnormal presentations
are more likely and account for a higher potential for cesarean
delivery. Other described complications include polyhydramnios, birth
depression, and congenital anomalies, including those related to
compression or constraint in utero.6