A 35-year-old woman developed severe hypertension resistant to antihypertensive treatment during the second trimester of pregnancy at 24 weeks gestation. Doppler ultrasonography achieved the diagnosis of idiopathic renal arteriovenous fistula in the left kidney associated with parenchymal hypoperfusion. A Caesarean section was performed 6 days after the diagnosis because of severe pre-eclampsia. After delivery, the symptoms disappeared. Fistula persisted after follow-up for over 1 year but with a dramatic decrease in its blood flow and normalisation of the left kidney hemodynamics. Nevertheless, embolisation was performed without complications to prevent recurrence during the next pregnancy expected by the patient.