I am new at OPKs, but have been trying to conceive for quite some time. Please help me out. My periods are every 21-24 days and about 8 days long. This all began after my miscarriage in March. When do you think I should start checking for ovulation? What day should I start? My doctors tell me soon after my period is over. I think that's too soon. I do have a tracker, but Im still confused. Please help me out. I just had a sonohysterogram yesterday, and I didn't want to begin my OPK today since Im still spotting from the procedure.