Well, a vaginal breech delivery can be pretty tough. Baby's head is the largest part of his body. When it comes out first, it stretches the cervix enough that the rest of the body comes out fairly easily afterwards. However, if the body comes out first (as with a breech baby), it might not stretch the cervix enough for the larger head to fit. In a vaginal breech birth, a prolapsed umbilical cord — when the cord goes through the birth canal before baby — is also more likely. A prolapsed cord can become pinched, which cuts off blood flow (and puts baby in serious danger).
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