Can hysterosalpingo foam sonography (HyFoSy) replace hysterosalpingography (HSG) as first choice tubal patency test: a randomized comparison (foam study)?

Abstract

Objective: traditionally, tubal patency testing during fertility work-up is performed by hysterosalpingography (HSG). Hysterosalpingo-foam-sonography (HyFoSy) is an alternative technique without radiation exposure and is less expensive than HSG. Globally, there is a shift towards the use of office-based diagnostic methods, such as HyFoSy. Here, we assess whether HyFoSy is as accurate as HSG in evaluating tubal patency and if it leads to comparable pregnancy outcomes. Design: multicenter prospective comparative study with a randomized non-inferiority design. Materials and Methods: participating women underwent both HyFoSy and HSG, in randomized order, by a physician unaware of the result of the first test (NTR 4746). In case of discordant results for HyFoSy/HSG, women were randomly allocated to either a management strategy based on HyFoSy or one based on HSG. Assuming 7% discordant results, we needed to recruit 1,163 participants (van Rijswijk et al., 2018). Primary outcome is ongoing pregnancy within 12-months after inclusion. Secondary outcomes are concordance between HSG and HyFoSy, pain scores, live birth, time to pregnancy, clinical pregnancy, miscarriage, multiple pregnancy, preterm birth. Results: between June 2015 and January 2019, a total of 1164 women were scheduled to undergo HSG and HyFoSy. At moment of writing, data on 97% was available. 2.3% of the women did not undergo any tests, 5.0% had HSG only and 0.6% had HyFoSy only. From the women who had both tests, 2.9% had an inconclusive HSG and 8.5% had an inconclusive HyFoSy (RR 2.3, 95%CI 1.6-3.2). In 0.8%, both tests were inconclusive. Among the women with two tests completed, 85% had concordant results (94.7% patent tubes, 3% with unilateral occlusion, 0.9% with bilateral occlusion, 1.4% with other findings). The mean pain score on the 1-10 VAS-scale was 5.4 (95%CI 5.2-5.6) for HSG compared to 3.0 (95%CI 2.9-3.2) for HyFoSy (p-value<0.001). Pain score of HyFoSy was not affected by the order of the tests (p=0.34). Of the 136 eligible women with discordant results, 108 women gave consent to be randomly allocated to management based on HSG (n=53) or HyFoSy (n=55). At moment of writing, data on the primary outcome were available in 58.5% of the HSG-group versus in 54.6% of the HyFoSy group. Ongoing pregnancy occurred in 30.2% of the women allocated to management based on HSG, and in 27.3% of the women allocated to HyFoSy (RR 1.1, 95% CI 0.6aG��Gǣ2.1). By October 2019, 90% of women will have complete one year follow-up. Conclusions: hyFoSy and HSG have a concordance of 85%, with HyFoSy experienced as significantly less painful and without the need of radiation exposure. In case of a discordant result, management based on the results of HyFoSy or based on the results of HSG lead to similar pregnancy outcomes. Reference: van Rijswijk J, van Welie N, Dreyer K, van Hooff MHA, de Bruin JP, Verhoeve HR, et al. The FOAM study: is Hysterosalpingo foam sonography (HyFoSy) a cost-effective alternative for hysterosalpingography (HSG) in assessing tubal patency in subfertile women? Study protocol for a randomized controlled trial. BMC women's health. 2018;18(1): 64