[Unusual twin pregnancy: one in the pseudo-unicornate uterus and the other in the rudimentary uterine horn. Discussion on the diagnosis and management during pregnancy].

An unusual twin pregnancy was diagnosed echographically at 18 weeks gestation and confirmed by magnetic resonance imaging. One foetus was in a pseudo unicornis uterus and the other in a rudimentary uterus cornu. The risk in such cases, as also reported in the literature, is rupture of the rudimentary cornu at about 20 weeks gestation. In this case the patient was carefully monitored to 23 weeks when the pregnancy in the rudimentary cornu stopped spontaneously. The foetus in the pseudounicornis developed normally to 38 week term. This exceptional observation emphasizes the risk of pregnancy in a blind uterus cornu.