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What is The diameter of fetal head, which comes in totally deflexed head : and explain in detail?
Circumferences of the head in different attitudes: -- Complete flexion Biparietal-suboccipito-bregmatic. Shape -- almost round 27.5 cm (11") -- Deflexed Biparietal-occipito-frontal. Shape -- oval 34 cm (13 1/2 ") -- Incomplete extension Biparietal-mento-veical. Shape -- bigger oval 37.5 cm (15") -- Complete extension Biparietal-submento-bregmatic. Shape -- almost round 27.5 cm (11") Reference: D C Dutta Textbook of Obstetrics 7th edition,page 85.