Hysterosalpingo-contrast sonography was compared with sonographically controlled selective tubal catheterization (STC) in 26 infertile women who complained of infertility. Both procedures were carried out on a single examination date. A group of 10 patients first underwent hysterosalpingo-contrast sonography followed by STC, while 16 first had STC followed by hysterosalpingo-contrast sonography. The main outcome measure was tubal patency. A total of 52 Fallopian tubes was assessed. Hysterosalpingo-contrast sonography showed 39 tubes (75%) and STC 46 (89%) to be patent, 13 tubes (25%) and six tubes (12%) were diagnosed to be proximally occluded, by means of hysterosalpingo-contrast sonography and STC respectively. Concordant diagnosis with both methods was made in 43 of 52 tubes (83%). When hysterosalpingo-contrast sonography was followed by STC, the concordance rate was 85%. When STC was followed by hysterosalpingo-contrast sonography, the concordance rate was 81%. In one patient the diagnosis of proximal occlusion of one tube as determined by hysterosalpingo-contrast sonography and STC had to be correlated in laparoscopy. In a patient, who after hysterosalpingo-contrast sonography and STC, was suspected to have bilateral proximal occlusion of the tubes, considerable bilateral proximal stenosis and distal occlusion was documented at laparoscopy. In conclusion, sonographically controlled STC may correct a misdiagnosis in cases where hysterosalpingo-contrast sonography leads to the finding of proximal tubal obstruction. The combination of hysterosalpingo-contrast sonography and STC as an out-patient investigation method for tubal patency assessment in infertile women avoids anaesthesia and radiation. For this reason we recommend the combination of sonographically controlled STC with hysterosalpingo-contrast sonography, at least in cases where proximal tubal occlusion is suspected after hysterosalpingo-contrast sonography. The influence of the order in which the two methods are used on the results of both should be investigated in a randomized study.