Ovulation Test Question

Katelyn
I've read some posts from people who say that you can't take an ovulation test with your FMU. I got Clear Blue Digital. It says that when you test to make sure you haven't peed in the last 4 hours. With the amount of water I'm drinking, that's next to impossible unless I use my FMU. Is there really a problem with using your FMU? I took one anyway tonight and got a negative, even though I should be close to ovulating. It was my first and I'm wondering if it was negative because it was really watered down. Anyone have any suggestions or advice? This is my first month TTC and I have lots of questions!