Ultrasonic study of tubal patency using 1.5% hydrogen peroxide as the contrast medium during hydrotubation was performed in 147 sterile women. Hysterosalpingography was also done for the same patients. In 42 cases, laparoscopic examination of the tubes was carried out to assess the accuracy of the above two diagnostic procedures. The correspondence rate between laparoscopic findings and ultrasonography was 88.0% and 60.0% with hysterosalpingography. The difference was statistically significant (P less than 0.05). Animal experiment did not reveal any untoward effect of 1.5% hydrogen peroxide on the local tissues exposed to the solution except a transient increase of lymphocyte infiltration and exudate. Regardless of its numerous advantages, neither hysterosalpingography nor ultrasonic examination can demonstrate minute pathologic changes in the lumen of the tube. The authors pointed out that ultrasonic study combined with laparoscopic examination is the best choice diagnosis for tubal abnormalities.