The recurrent non-immunological hydrops fetalis is classified as a separate entity. It is usual to differentiate between the chylous and the idiopathic form. The case presented indicates that the recurrent non-immunological hydrops fetalis should not be seen as an idiopathic but as a chylous form. Only in enterally fed children the initially amber coloured pleural effusion becomes opaque and the triglycerides are then elevated. This points to a fault in the development of lymph vessels.