hi, my tests say you will ovulate in the next 12 to 36 hours so i think anytime around then would be fine. Sperm can live fora while so once should be fine. I wouldn't do it too many times as the sperm count can go down if you don't wait at least 24 hours between times. I would also bd 2 says later just to make sure you didn't ovulate on the 36 hour end rather than the 12. Good luck
Thanks for the reply......I guess tomorrow morning will be OK and maybe Mon. night just to be safe!
I am also on cycle day 13 and I am using opts for the first time this cycle however I am not getting darker lines so good luck to you.
I don't ovulate until really late in my cycle (day 25 of 25 day cycle) so not everyone will ovulate on the same time. Try not to use the test everyday as you will use them up to quick. Good luck
LACh1 is right....you'll rip thru those things like mad!, if you use www.babymed.com (Fertility Calander), it will tell you when to start testing.....If you have a normal 28 day cycle I think that it told me to start testing on Thurs.......
sorry i meant day 25 of a 35 day cycle lol that would be very weird