Opk different result

Ayan • Tue, Aug 04

Hi so my husband and I took a 2 year break from ttc after out miscarriage and now we have decided to try again. I usually get a positive opk around cd 15-16. I am on cd 12 and I got two different results from the same urine. Does anyone know why? The bottom one was dipped a just a second longer than the top one.