Abstract

PIP: Early abortion traditionally referred to abortion within 12 weeks of gestational age, but it is necessary to divide it into 3 stages: ultra early abortion for the one within 5 weeks of gestational age; very early abortion for the one within 8 weeks; early abortion for the one between 8 and 12 weeks. Progress and development in them are of IVF-ET and GIFT necessitated redefining pregnancy and resulted in great number of terms related to early pregnancy and abortion, which are not standardized and sometimes confusing. In connection with IVF-ET research, the following 3 stages of early pregnancy are recognized by Japanese doctors. Biochemical pregnancy is when plasma level of beta HCG is above norm. Early clinical pregnancy is when the Gestational sac is detected by ultrasonography but the heat beat of fetus is not yet confirmed. Established clinical pregnancy is when the heart beat of the fetus is confirmed via ultrasonography. Early abortion is divided into 2 stages: subclinical abortion (menstrual abortion), which is menstrual like fetus wastage in biomedical pregnancy, and clinical abortion in which a blighted ovum is detected by ultrasonic examination. Classification above is simple and easy but it heavily relies on measurement methods, results of which often fluctuate and are subject to change. It seems desirable to classify early abortion according to gestational age (GS). GS may be detected as early as 4 weeks, is above 10 mm in the maximum diameter at 5 weeks, and is detected in all cases at 6 weeks. Human chorionic gonadotropin (HCG) test by 1000 IU/1 sees positive response in almost all cases at 6 weeks, while HCG by 200 IU/1 sees the same at 5 weeks. The heart beat of the fetus is believed to commence at 4 weeks but it is not detected by ultrasonography at the earliest till the end of 5 weeks and in all cases till 8 weeks. The classification of ultra early abortion, very early abortion and early abortion, is based on above findings.