I have been ttc for a while now an I always track when I ovulate yes <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">eve</a> helps some but is always a little off well I've been using the brand "answer" an the lines always start out light then get dark then fade back out...well since the first day I started testing they have all been positive this has never happened we have been using preseed for a few months now could that affect it...also about two weeks or so ago my doctor started me on metformin to treat my polycystic ovary syndrome...my doctor thinks that why I'm not pregnant yet...but it's supposed to take 4 to 8 weeks to work so would that affect my tests???