I purchased this monitor to figure out my ovulation patterns after 2 failed IUI’s. I discovered that my LH surge is a gradual onset and that we inseminated far too early. Now that we know which day I actually ovulate as it confirms my fertile window, I am hoping to be more succesful on my next IUI. I did have 1 “dud strip” out of the pack, but overall I like it. I just hate having to take my phone apart each morning to use it.