cross-birth

from The Century Dictionary.

• noun A birth in which the child lies transversely within the uterus.

from the GNU version of the Collaborative International Dictionary of English.

• noun (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.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun medicine A birth in which the fetus is positioned with neither the head nor the feet lying in the direction of the birth canal.