Birth control and breakthrough bleeding

It may look like light spotting or bleeding outside the expected withdrawal bleed. It does not by itself show whether contraception is working; pregnancy protection depends on the method being used correctly.

Hormonal contraception changes the uterine lining. While the lining adjusts, small areas may shed at unexpected times. Bleeding can also follow missed pills, late doses, vomiting, diarrhoea, or medicines that interfere with a contraceptive method.

Other explanations can exist alongside birth control. Cervical irritation, pregnancy, infection, and growths inside the uterus may cause unexpected bleeding. Chlamydia can present with bleeding between periods or after sex, while endometrial polyps may present with irregular bleeding. Neither symptom alone identifies the cause.

Continue the method according to its instructions unless a clinician advises otherwise. Check the missed-dose guidance supplied with your contraception, because the action needed differs by method and timing. Use additional contraception if that guidance recommends it.

Record bleeding days, flow, pain, missed or late doses, medicines, and bleeding after sex. Take a pregnancy test if pregnancy is possible. Arrange a routine appointment if the bleeding keeps returning, becomes troublesome, begins after a previously settled pattern, or follows sex.

Get urgent medical help for heavy bleeding with fainting, marked dizziness, breathlessness, severe or worsening pelvic pain, shoulder-tip pain, or a positive pregnancy test with pain or bleeding. These symptoms require prompt assessment, including for pregnancy complications.

Seek timely clinical advice for fever, unusual or unpleasant-smelling discharge, pain during sex, bleeding after sex, or symptoms of anaemia such as unusual fatigue and shortness of breath. Testing may include a pregnancy test, infection testing, an examination, or imaging depending on the pattern.

Ask whether your bleeding pattern fits your specific method, whether any missed doses or medicines reduced protection, and when a pregnancy test is appropriate. You can also ask whether infection testing or an examination is needed and what alternatives might offer a more acceptable bleeding pattern.