Bleeding a few days after taking birth control pills is usually endometrial withdrawal bleeding, a sign of successful birth control and a relatively common phenomenon.
Endometrial withdrawal bleeding can occur if the dose of progesterone contained in the pill is relatively high. It is usually caused by a high level of progesterone at the time of taking the pill and a low level of progesterone for a period of time after taking the pill, causing withdrawal bleeding, which is a normal phenomenon. The bleeding is usually less.
However, not all people will bleed after taking the emergency contraceptive pill. No bleeding does not mean contraceptive failure, and bleeding does not mean contraceptive success. It is still possible that around 5-10% of women will have a contraceptive failure and have an unplanned pregnancy.
If you have heavy or dripping blood for a few days after taking birth control pills, it is recommended that you seek timely medical attention to clarify the cause of the problem and actively treat the symptoms to avoid delaying the condition.