Im bleeding on birth control after my period. zafemy, started 3-4 months ago. bleeding started 3 weeks ago, after changing a patch. had my period, bleeding stopped, but patch on and its started again. why?

Most commonly, breakthrough bleeding is caused by inadequate progesterone. Finding the right birth control for each person can be a challenge. If patches are applied to areas where skin is thicker, or if the adhesive causes a mild allergy - the medication contained cannot be absorbed properly. Tell your prescribing physician the issue you are having 3 months out, and s/he will likely change it.