The Collaborative International Dictionary
Cross-birth \Cross"-birth`\ (kr[o^]s"b[~e]rth`), n. (Med.) Any preternatural labor, in which the body of the child lies across the pelvis of the mother, so that the shoulder, arm, or trunk is the part first presented at the mouth of the uterus.
Wiktionary
n. (context medicine English) A birth in which the fetus is positioned with neither the head nor the feet lying in the direction of the birth canal.
Usage examples of "cross-birth".
Women in mortal labour with cross-births have been brought there and laid on the grave from which she was taken, where we buried Rhisiart, and their children have been soothed into the world whole and perfect, with no harm to the mothers.
That I was a girl presented a minor problem, since the majority of such cross-births are male and the offspring trained from childhood for government service.