Confused with digital opks...

Theresa • Married for 3 years, Cat Mom of 10 and an all cat Veterinarian, TTC baby #1 for over 1 year..... ♥️♥️

Hi ladies, I am super confused about the clear blue digital advanced opks and when to use them. It says on the directions to use the first urine after longest sleep. So this is taking them first thing in the morning ???? Mine today in the morning was negative but then the strips showed a positive later this morning.. . Don't know what to believe...help please!!!