Diagnosis of Placenta Previa and Low-lying Placenta By Means of B Scan / 昆明医科大学学报

ABSTRACT

From January 1987 to April 1991, we used the ultrasonography in the diagnosis of placenta previa of 197 cases. The diagosis of placenta previa is made to assess the relationship of the lower margins of the placenta and the internal os. There were total 74 eases of placenta previa (37.6%), 37 cases of (18.8%) partial placenta previa, 46 cases of low-lying placenta (23.4%), and 40 cases of "relative low-lying placenta" (20.2%). The high ratio diagnosis of the total placenta previa was made at 28-36 weeks.(P