What should you know about progesterone breakthrough bleeding?

Bleeding may follow a new medicine, a change in dose or schedule, missed doses, or the transition to a different hormonal pattern. It can be light spotting or resemble a period. The reason is not always the progesterone itself: pregnancy, infection such as chlamydia, cervical changes, or an endometrial polyp can also cause bleeding. The pattern, timing and amount help a clinician decide whether examination or testing is needed.

Record when bleeding starts, how long it lasts, whether it follows a dose, and whether you have pain, discharge or dizziness. Take progesterone exactly as prescribed unless your prescriber tells you otherwise; do not double a missed dose without advice. Arrange a review if bleeding continues, returns after settling, happens after sex, or worries you. Mention pregnancy possibility and all contraception or hormone products.

Seek urgent care for bleeding that is heavy or rapidly worsening, severe pelvic pain, faintness, marked weakness, fever or feeling very unwell. Bleeding after menopause should be assessed, even when it is light. Sudden severe pain with a possible pregnancy needs urgent evaluation.

Ask whether your schedule is intended to produce a withdrawal bleed, how long adjustment may take, whether a pregnancy test or pelvic examination is appropriate, and which changes should trigger an urgent call.