P12.11: Discordant VACTERL association in a dichorionic twin pregnancy after insemination

Abstract

VACTERL is an acronym for a nonrandom malformation sequence including V (vertebral anomalies), A (anal atresia), C (cardiac anomalies), TE (tracheoesophageal fistula or esophageal atresia), R (renal anomalies) and L (limb defects). Diagnosis of the condition requires the presence of at least three of the seven cardinal anomalies. The most frequent defects are the tracheoesophageal fistula and anal or vertebral anomalies. Although VACTERL occurs sporadically, it is more often observed in pregnancies complicated by diabetes. Prenatal ultrasound diagnosis is challenging. We report a case of prenatally suspected VACTERL association in the second trimester. A 35-year-old gravida 1 with dichorionic twin pregnancy (after insemination) was referred at 20 weeks of gestation. While the first twin appeared to be normal, the 2D scan of the second twin revealed an overriding aorta, unilateral renal agenesis and single umbilical artery. In addition, 3D ultrasound of the fetal spine with maximum render mode identified the presence of hemivertebra at L5. Thus, discordant VACTERL association was suspected. Premature rupture of membranes and breech presentation of the first twin necessitated a Caesarean section at 34 w.g. The affected neonate was female, weighing 1750g. No anal atresia or tracheoesophageal fistula was present. DNA analysis revealed normal karyotype. All prenatally diagnosed findings and VACTERL association were confirmed after birth.