Is it normal to bleed after taking emergency contraception?

Patient's question:

Having sexual intercourse 2 days after menstruation, then taking emergency contraception, bleeding 2 days later, and the bleeding volume was relatively large

Doctor's answer:

Withdrawal bleeding caused by birth control pills. Birth control pills may temporarily cause a one-time increase in hormone levels in the blood due to temporary use, followed by withdrawal bleeding after the levels drop,. Withdrawal bleeding caused by birth control pills usually improves within 2–5 days and does not require treatment. It should now be considered a safe period, and sexual intercourse should not lead to pregnancy.