The increased incidence of fetal abnormalities in cases of placenta previa

Abstract

Summary In this paper I have attempted to show that fetal monsters and deformities occur more frequently in cases of placenta previa than otherwise. Evidence has been presented from embryologists and others to show the great role played by environment in the etiology of monsters. Clinical data to support this are obtained from the very high incidence of malformed embryos and twins in eases of tubal pregnancy where the decidual reaction is only slightly developed. Likewise, it is pointed out that the decidual reaction in the isthmus of the uterus is poorly developed and that this plays a role in the causation of abnormal fetuses in cases of placenta previa. I collected data covering 369,597 labor cases and found that whereas the incidence of fetal monsters was 0.94 per cent for the entire group, the frequency of fetal deformities in the 3,423 cases of placenta previa in essentially the same group was 2.75 per cent. If to these 3,423 cases are added 1,023 cases of placenta previa which I collected from the literature, the incidence of fetal monsters and deformities for the entire group of 4,446 cases of placenta previa (representing approximately 4 million obstetric cases) was 2.5 per cent as contrasted with 0.94 per cent for all obstetric cases. In approximately half of all the abnormal fetuses associated with placenta previa, the deformity consisted of defects which can easily be recognized by means of x-ray pictures. Hence, in every case of placenta previa an x-ray picture should be taken. The detection of fetal monsters will usually lead to conservative treatment although cesarean section will have to be employed in some cases in spite of the fetal abnormality.