Transvaginal ultrasonography was done on 26 pregnant women ranging from 5 to 27 weeks of gestation and 12 patients with gynecologic diseases. In early gestation, significant correlations were found among gestational age, crown-rump length, diameter of yolk sac and fetal heart rate. The maximal length of the gestational sac did not correlate with any other parameter. Transvaginal image quality was better in 76.2% in obstetric field and in 66.7 % in gynecologic field, as compared to findings with conventional abdominal ultrasonography, respectively. Fine structures and individual organs were better evidenced transvaginally. Therefore, transvaginal ultrasound affords pertinent information complementary to that obtained with the transabdominal technique.