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What is Pelvis justo major and explain in detail?
Pelvis justo major (also called "Giant Pelvis") is a rare condition of the adult female pelvis where the pelvis flairs above the Iliopectineal line. It is 1.5 or more times larger than an average pelvis in every direction and is at least 42 cm (16.5 inches) biiliac width. Even though this condition is classified as a congenital abnormality, it is not a medical disease or abnormality of the pelvis (as the pelvis is a true gynecoid shape, only larger). 
Women with this condition, at the time of delivery, may have a precipitous birth. There is virtually no resistance of the huge pelvic opening to the size of a newborn so only the soft parts resist the birth. With a huge Justo Major Pelvis, there is no pelvic bone "molding" of the fetal head. With the average pelvic size (2/3 or less Justo Major size) the usual pelvic molding process slows the birth, resulting in a slow and gradual stretching of the vaginal opening for primiparous women. When a huge Justo Major Pelvis allows such an extremely rapid vaginal birth, there can be tears of the perineal soft tissues. At the time of delivery the strong uterine contractions and maternal bearing down almost instantly overwhelm the integrity of a tightened and previously unstretched vaginal orifice