From Routine to Rare: Uncovering Double Aortic Arch During Prenatal Care

Methods: This is a retrospective cohort study examining pregnancies complicated by FGR at our facility from 2023 to 2024.Demographic factors, pregnancy and neonatal outcomes were obtained from medical records.Pregnancy outcomes among those with FGR based on AC were compared to those with FGR based on EFW and AC.Placental weights were also compared.Results: 76 patients were included in the final cohort with 74 live births.Notable demographic factors and pregnancy outcomes are displayed in Table 1.71 patients were diagnosed with FGR based on AC alone, and 5 were diagnosed based on EFW and AC.Those diagnosed using EFW had significantly increased rates of intrauterine fetal demise (IUFD) (40%, p 0.004) and moderate-to-severely abnormal umbilical artery (UA) Doppler results (60%, p 0.007).Rates of oligohydramnios, hypertensive disorders of pregnancy and mean placental weight did not differ significantly.Conclusions: The majority of FGR diagnoses were based on AC only.FGR based on EFW was associated with higher rates of outcomes associated with uteroplacental insufficiency, suggesting that FGR based on EFW may represent a more severe form of growth restriction.Given the small sample size, further investigation is warranted to determine whether FGR based AC alone can be considered lower risk for adverse outcomes and may therefore require less intensive surveillance.