Breakthrough bleeding (
BTB) is any of various forms of
vaginal bleeding, usually referring to mid-cycle bleeding in users of
combined oral contraceptives as attributed to insufficient estrogens. It may also occur with other hormonal contraceptives. Sometimes, breakthrough bleeding is classified as abnormal and thereby as a form of IMB. In the context of
hemophilia, the term describes a bleeding that occurs while a patient is on
prophylaxis.
Presentation The bleeding is usually light, often referred to as "spotting," though a few people may experience heavier bleeding. It is estimated that breakthrough bleeding affects around 25% of
combined oral contraceptive pill (COCP) users during the initial 3 to 4 months of use, it then usually resolves on its own.
Mechanism Breakthrough bleeding is commonly due to 4 factors: physiologic effects of OCs on the endometrium, OC-related parameters, (dose, formulation, and regimen), patient behavior, (compliance, using concomitant medications, and smoking) and benign or malignant pathology.
Treatment Breakthrough bleeding that does not resolve on its own is a common reason for women to switch to different pill formulations, or to switch to a non-hormonal method of
birth control. ==See also==