VP04.05: Associated anomalies and outcome in cases of absent ductus venosus diagnosed at 11–13+6 weeks' scan

Abstract

To determine the incidence of associated anomalies and outcomes in absent ductus venosus in pregnant women undergoing the nuchal translucency scan (NT) at 11-13+6. A retrospective case record-based study of prospectively collected data from pregnant women attending NT scan at a single centre in western India. The assessment included measurement of NT, evaluation of nasal bone (NB), ductus venosus (DV), tricuspid regurgitation (TR), according to the Fetal Medicine Foundation protocols. The detailed anatomical evaluation was done in all patients. When the DV was not seen, the umbilical vein was traced to evaluate it's joining with systemic veins. The incidence of absent ductus venosus and the association with anomalies were determined. The cases where the pregnancy was continued, were followed up in postnatal life. The records of 2884 first trimester ultrasound examination from December 2016 to December 2019 were analysed. Absent ductus venosus was detected in 10 (0.35 %, 95 % CI: 0.19, 0.64) pregnant women . Eight (80.00 %) women were primigravida. Seven (70 %) had a normal NT thickness. Five (50.00 %) of these 10 fetuses had associated cardiac anomalies and one had radial ray defect. One fetus had bilateral jugular sacs, absent NB and increased NT which was confirmed as trisomy 21 after amniocentesis. In 9 cases the umbilical vein was opening in inferior vena cava, while in 1 case it was opening in iliac vein. All seven abnormal pregnancies were terminated. The remaining three fetuses with isolated absent DV were followed, one fetus had intrauterine demise at 29 weeks. The other two were born normal. One of these babies died at 6 months of age because of pneumonia. The other baby is normal till date. No postnatal sonography was done in these two live-born children. Assessment of DV during NT scan is very important. Absent DV is associated with cardiac, extracardiac and chromosomal abnormalities. Absent DV is associated with adverse outcome. Absent DV may be present even with a normal NT.