Early sonographic diagnosis of fetal midline disruption syndromes.

This is a study of different severe fetal body wall defects and other abnormalities which were observed by transvaginal ultrasonography in six fetuses at 11 4/7 to 15 weeks' gestation. The main abnormalities were acrania, kyphoscoliosis, neural tube defect, ectopia cordis, diaphragmatic hernia, and ventral wall defect with exstrophy of the intestine, liver, and kidneys. A normal amniotic sac was noted in three cases. In one case, the amniotic sac could not be defined and in the other two cases, some of the abdominal contents were located outside the amniotic sac. The possible aetiology of these fetal malformations is discussed.