HSG test- reason?

Jessica • TTC #1

I am having my HSG done Monday after 2 letrozole cycles, one with <a href="https://glowing.com/glow-fertility-program">IUI</a>. I have PCOS so I think my dr thought I’d get pregnant once he got me to ovulate. That didn’t happen so now testing tubes. I have no previous abdominal surgeries or pregnancies or infections or endometriosis that should cause this. Has anyone else also not really had a cause but still had blocked tubes??