We present an overview of the common types of tubal patency tests, with a focus on hysterosalpingo-foam sonography (HyFoSy). Current evidence suggests that HyFoSy is an accurate alternative to X-ray hysterosalpingography (HSG) for outpatient tubal evaluation in women who are at low risk for tubal disease. It may be superior to saline hysterosalpingo-contrast sonography (HyCoSy) in excluding tubal occlusion. A hyperechogenic medium may enhance contrast visualization and enable clearer delineation of tubal anatomy. This may enhance confidence in the diagnosis of tubal patency, reduce false occlusion results, and improve the diagnostic yield of the test. It would be reasonable to deduce that HyFoSy would have similar performance characteristics as HyCoSy with other positive contrast agents. The available evidence supports the accuracy of HyFoSy compared to other forms of tubal investigation. We suggest a decision-making pathway based on the most current professional recommendations and available evidence. However, in this article, we do not provide a definitive exposition of the methods used for investigating tubal patency. Rather, we explore the contexts in which the various investigations are most and least suitable, and identify their strengths and limitations. Finally, we also discuss challenges encountered when performing tubal contrast sonography in clinical practice, including the problem of false occlusion results.
Keywords: hysterosalpingo-contrast sonography; hysterosalpingo-foam sonography; infertility; tubal occlusion; tubal patency testing.