Ultrasound in the diagnosis of fetal malformations. Implications for obstetric management.

The prenatal diagnosis of congenital malformations through ultrasonography leads to major considerations regarding subsequent pregnancy management. These diagnoses are useful in reaching decisions concerning elective abortion, planning the time and method of delivery, and arranging for appropriate support personnel. Although the possibility of fetal anomaly must be considered in all obstetric ultrasonograms, review of 56 malformations diagnosed prenatally found that 31 were studied because of uterine size incompatible with gestational age. Polyhydramnios was associated with 24 of these cases. Multiple fetal abnormalities were found postnatally in 24 of the 51 cases in which one or more malformations were diagnosed through ultrasonography, emphasizing the need for careful counseling and follow-up examination.