Is it ensure, insure, or assure?
c.1300, "go astray;" mid-14c., "come to harm, perish;" of persons, "to die," of objects, "to be lost or destroyed," from mis- (1) "wrongly" + caryen "to carry" (see carry (v.)). Meaning "deliver unviable fetus" first recorded 1520s; that of "fail, come to naught" (of plans or designs) is from c.1600. Related: Miscarried; miscarrying.
miscarry mis·car·ry (mĭs'kār'ē, mĭs-kār'ē)
v. mis·car·ried, mis·car·ry·ing, mis·car·ries
To have a miscarriage; abort.