The value of transvaginal 4-dimensional hysterosalpingo-contrast sonography in predicting the necessity of assisted reproductive technology for women with tubal factor infertility

Background: More than 50 million women suffer from infertility worldwide, among whom 30% have associated fallopian tube pathology. Fortunately, the diagnostic accuracy of tubal patency has been enhanced with the consistent development of ultrasound imaging technology, especially the invention of transvaginal 4-dimensional hysterosalpingo-contrast sonography (TV 4D HyCoSy). However, detailed imaging data for evaluating the tubal condition for spontaneous conception and assessing the necessity of assisted reproductive technology (ART) have yet to be amassed. Methods: Patients with tubal factor infertility (TFI) who received TV 4D HyCoSy were recruited for this study. They were divided into two groups according to the method of conception: the natural pregnancy group (patients who naturally conceived within 3 months after TV 4D HyCoSy) and the assisted reproduction group (patients who failed to conceive naturally within the 3 months but successfully conceived through ART). Logistic regression analysis was performed to examine the data obtained from participants' medical history and TV 4D HyCoSy investigation. Results: Of the initial 1,433 women, 348 were excluded due to exclusion criteria or lack of follow-up. A total of 1,085 TFI patients were finally included, with individuals in the natural pregnancy group accounting for 27.74% (n=301), and those in the ART group accounting for 37.33% (n=405). The age was younger and the duration of infertility was shorter in the group of women who conceive spontaneously after TV 4D HyCoSy (P<0.05). In terms of imaging data, their endometrial thickness was thinner, right fallopian tube wall was more intact, morphology of the right fallopian tube was smoother, and their ovarian motility (bilateral), fallopian tube visualization (bilateral) and overflow condition of the contrast agent from the fimbriae of fallopian tube (bilateral) were better. In addition, the resistance of the contrast agent injection was less likely to be persistent, reflux was less likely to happen and 0/1 dispersion of the contrast agent around the ovary (bilateral) were more likely to be annular (P<0.05). Conclusions: The imaging data gathered from TV 4D HyCoSy in TFI patients were comprehensive, which suggested that TV 4D HyCoSy could have potential to be used to assess the necessity of post-HyCoSy ART intervention in patients with TFI. This could be of benefit in reducing the incidence of overtreatment and potential complications of ART.