Newbie at OPKs


Okay so I am new to taking opks. Let's just say hypothetically speaking you could only have sex ONCE during your fertile window. You get your peak on the 10th of June. What day would you choose to BD? On peak day, day before, or day after? Asking for myself as I only got to bd about 2 hours after getting my very first positive opk and it was a blazingg peak. My husband had to leave for work that evening for the rest of the week. I know it only takes one time but I'm a complete pyscho and need others opinions and reassurance lol. Thanks in advance.