This was my first cycle on Letrozole after a few failed cycles with clomid.(I did ovulate with clomid but my periods were still off and not has effective as she would have liked) My ovulation tests looked to be gearing up and I though I would ovulate tomorrow or Saturday. Did another this afternoon and the line had almost vanished. 😭😭😭 I'm so upset. Has this happened to many people on Letrozole?