[1] In some women, menstrual spotting between periods occurs as a normal and harmless part of ovulation.
Some women experience acute mid-cycle abdominal pain around the time of ovulation (sometimes referred to by the German term for this phenomenon, mittelschmerz).
If spotting continues beyond the first 3-4 cycles of oral contraceptive use, a woman should have her prescription adjusted to a pill containing higher estrogen:progesterone ratio by either increasing the estrogen dose or decreasing the relative progesterone dose.
[citation needed] 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.
[8][9] 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.