Despite reports that women experience fewer side effects while taking minipills, breakthrough bleeding is still possible. These pills make the uterine lining thinner, which weakens the tiny blood vessels and can cause bleeding. Also, one of the most notable side effects of progestin-only pills is irregular menstruation.
Reports estimate that 13 out of 100 users become pregnant within a year of taking POPs or minipills.
You are smoking
One of the causes of breakthrough bleeding is smoking. According to experts, women who smoke are more likely to experience bleeding while taking extended-cycle birth control pills.
Other causes of breakthrough bleeding
Besides the reasons discussed above, please note that the following can also lead to unexpected bleeding while taking oral contraceptives:
- Diarrhea and vomiting, since they impair the absorption of the oral contraceptive pills.
- Medications or supplements that interfere with the contraceptives. Examples include antibiotics and St. John’s wort.
Bleeding in between periods
Women who do not take birth control pills, or those who have stopped taking them, may still experience unscheduled or unexpected bleeding. The common causes of spotting between periods are:
Spotting can also be an early sign of pregnancy since implantation, the process where the fertilized egg attaches to the lining of the uterus, can cause bleeding or spotting. Similarly, light bleeding is also a warning sign of an ectopic pregnancy and miscarriage.