Is intermenstrual bleeding a common side effect on the combined oral contraceptive pill (OCP)?
Yes. Intermenstrual bleeding is breakthrough bleeding or spotting which starts and finishes within the pill-taking interval .On average, spotting accounts for two-thirds of the bleeding episodes. The likelihood of intermenstrual bleeding is greater during the first three cycles of combined OCP use. The lowest incidence of breakthrough bleeding appears to be with formulations containing Levonorgestrel, Norgestimate and Desogestrel. It is also important to consider cervicitis (chlamydial or other), timing of pill ingestion (should be consistent each day), and possible reasons for pill malabsorption in assessing breakthrough bleeding. Smoking has also been associated with an increase in intermenstrual bleeding. Clinical observations indicate that a delay of even a few hours of ingestion can result in breakthrough bleeding. The presence of intermenstrual bleeding, however, does not by itself imply lower contraceptive effectiveness.
