Why would Ovia predict AF later than luteal phase?

[Rainyshowers]

My luteal phase is 11days based on Ovia app suggested fertile window, cervical mucus and last month I used opk and AF came 11days later. My cylce is typically 31-33 days long. I'm now on cylce day 31 but had a positive opk earlier in the month so I'm 13dpo today. But I took a pregnancy test this afternoon and it's negative. Luteal phases are pretty set from what I've read so where is AF as my luteal phase is now 13 days. And why does Ovia predict AF for day 33 of my cycle which would give me a 14 day luteal phase? So confused....

Well, a positive OPK can come one or two days before ovulation. You can also get a positive OPK and not ovulate. Sometimes the body prepares to ovulate then doesn't, and then ovulates a few days later instead. It could be you just ovulated a day or two later than you think.

I don't trust Ovia's prediction one bit. I have a really similar cycle to you. I did OPK's which were positive around CD14-16 so didn't bother taking any more in the month and well I conceived around CD26, the day I actually ovulated! If you have irregular cycles I would continue using OPK's and track them all month until you know when roughly you ovulate, it was a huge shock and a bit of luck for me that I conceived when I did but completely possible. Ovia predicts based on a 'normal' cycle which there is no such thing :)
Good luck! X

So were your positive opk on cd14-16 wrong If you the conceived on cd 26? How did you know you conceived so late in your cycle?

They must have been! Or weren't dark enough to be proper positives like I thought! I found out on my first scan, based on LMP I should be 2 weeks ahead of what I am but baby is progressing perfectly and they can date when you conceived based on babies size :)