Abstract
The "lean" umbilical cord (also known as thin-cord syndrome) is a comparatively rare anomaly of the umbilical cord, which has seldom been described in the medical literature. We report on a 35-year-old women who presented to us at 29 + 4 weeks gestation with vaginal bleeding and cervical incompetence subsequently complicated not only by premature rupture of membranes but also acute placental insufficiency requiring emergency caesarean section under general anaesthesia at 31 + 2 weeks gestation. At surgery no obvious cause for the acute placental insufficiency - such as placental abruption, cord prolapse or true knot of the umbilical cord - was found. Other possible causes such as vasa praevia or placenta praevia had previously been excluded sonographically on admission for vaginal bleeding. The only notable intraoperative finding was a macroscopically extremely thin umbilical cord.