Causes of Prematurity

UTERINE bleeding during pregnancy may be a symptom of various pathologic conditions. A diagnosis of premature separation of the placenta or of placenta previa can be made in some instances, but in others a definite underlying lesion is difficult to ascertain. The incidence of premature delivery is generally elevated among women who suffer from any of the conditions causing uterine bleeding during pregnancy. In 20 previous reports in the literature¹the incidence of placenta previa varied from 1.3 to 9.0 per cent among the mothers of premature infants; premature separation of the placenta from 0.2 to 5.1 per cent, and bleeding from unstated causes from 1.2 to 18 per cent. In our preliminary study²bleeding from undetermined causes was found to occur in a significantly greater number of mothers of premature infants than in those of full term infants. The group of patients with placenta previa or with