Doctor why my period is don't missing even my ovulation predictor is negative?if every women have getting every month correct ovulation?

Usually: I believe this answers your question- (if not please re submit). Periods that are predictably regular are most often associated with ovulation, however you can have anovulatory cycles with "relatively" regular periods. Ovulation kits use LH (lutenizng hormone) elevations to track ovulation. See your doctor to check hormones if you are having concerns.