OC20.07: *Significance of ductus venosus Doppler on monochorionic pregnancies with type III selective fetal growth restriction

Selective fetal growth restriction (sFGR) complicates 10% of all monochorionic pregnancies. Type III sFGR has intermittent umbilical artery Doppler abnormalities and optimal management remains controversial. Our centre offers expectant management with inpatient surveillance once fetal viability is anticipated. Our aim was to assess the impact of abnormal ductus venosus Doppler waveforms on delivery indications and outcomes. This is a retrospective cohort analysis of monochroic twin pregnancies >26 weeks' gestation complicated by sFGR, managed at a tertiary centre from 2015-2023. All patients were offered inpatient antenatal surveillance between 26-28 weeks' gestation and fetal monitoring. Ductus venosus (DV) Dopplers flow patterns during evaluation with absent or reversed “a” waves were considered abnormal. During the study period, 35 monochorionic twin pregnancies >26 weeks' gestation complicated by sFGR were managed in our centre. 60%, (21/35) were Type III and 8/21 of these, also had an abnormal DV patterns. Type III sFGR fetuses with abnormal DV Dopplers delivered at a significantly earlier gestational age (29 [28, 30] vs 33 [31, 34] weeks, p = 0.004) and more likely to be delivered for spontaneous fetal heart rate decelerations of the sFGR twin (75% vs 21%, p = 0.02) (see figure 1). Abnormal DV Dopplers is a common finding in pregnancies complicated by sFGR type III. Although it does not signify immediate fetal compromise, it is associated with earlier gestational age at delivery and increased risk of fetal distress leading to an emergency delivery when compared to sFGR type III cases with normal DV Doppler waveforms. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.