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What is Persistent occipitoposterior is common in the following type of pelvis: and explain in detail?
In more than 50% of cases, the occipito-posterior position is associated with either an anthropoid or android pelvis. Persistent occipitoposterior is an abnormal mechanism of the occipito-posterior position where there is malrotation of the occiput posteriorly towards the sacral hollow (occipito-sacral position). Delivery may occur spontaneously as face-to-pubis but arrest may occur in this position and is called occipito-sacral arrest. Ref: Textbook of Obstetrics by D C Dutta, 6th edition, Page 365, 369.