Hello, I went through your query, The presence of absent end diastolic flow (AEDF) can benormal in early pregnancy (up to 16 weeks). In mid to late pregnancy it usually occurs as a result of placental insufficiency . Flow in the umbilical artery(ies) should be in the forward direction in normal circumstances. If placental resistance increases, the diastolic flow may reduce, later becoming absent and finally reverses. The most common association would be intrauterine growth retardation of baby,, few others too, please talk to your doctor regarding this.