Does a probability of breech presentation of more than 50% exist among diseases and medical conditions?

The aim was to study the effect of twin gestations in a uterus with 2 bodies on the probability of breech presentation at delivery. The hypothesis was that the probability of breech presentation was not higher than 50%. A review was undertaken of MEDLINE (1966-2004) and of the article reference list for statistical analysis of presentation at delivery among twins in a normal uterus, singleton gestations in a uterus with 2 bodies, and case studies of twins in a uterus with 2 bodies.