[Significance of transvaginal ultrasonic examination in the first pregnancy trimester]

The authors report their results obtained by performing transvaginal sonography in 180 patients in the first trimester of pregnancy. It has been found that both normal and pathological cases could be diagnosed 1 week earlier than had been possible with transabdominal method. Minimum size of the intrauterin gestational sac was found to be 3 mm. Cardiac activity could be evaluated in embrios with a size of 7 mm or greater in all cases. According to them the diagnosis of blighted ovum and missed abortion seems to be confirmed when an "empty sac" is larger than 20 mm, or the absence of heart motion is detected in an embrio greater than 10 mm, without repeated scan. High sensitivity was found in ectopic pregnancies especially in unruptured cases. The possibility of qualitative analysis of "free fluid" in Douglas pouch and diagnosis of congenital anomalies in very early pregnancy are promising. Transvaginal sonography is recommended in all cases when transabdominal technique is equivocal.