[Congenital choledochal cyst. The value of systematic ultrasound screening starting in the second trimester of pregnancy (author's transl)].

: Routine obstetrical ultrasound carried out in the 20th week of amenorrhoea made it possible to identify a septate abdominal cyst which was non-urinary in origin and situated in the right hypochondrium. It was difficult, armed with this information, to be sure from which organ the cyst derived. The secondary diagnosis of a congenital cyst of the bile duct was made at laparotomy carried out a few hours after birth.