Why does perimenopause cause missed period?

Perimenopause is a transition in which ovarian activity becomes less consistent. Estrogen may fluctuate, and progesterone may not rise in the usual way when ovulation does not occur. The uterine lining can then shed later than expected, shed differently, or not produce obvious bleeding in that cycle. A missed period has other possible explanations, including pregnancy, stress, weight change, intense exercise, thyroid problems, polycystic ovary syndrome, and some medicines.

Mark expected and actual bleeding dates and note pain, spotting, hot flushes, or other symptoms. If pregnancy is possible, use a pregnancy test and repeat it or seek advice if uncertainty remains. Keep taking prescribed medicines unless a clinician tells you otherwise. A healthcare professional can review your history and decide whether an examination or tests are appropriate.

Make an appointment if missed periods recur, come with new pain or unusual discharge, or are worrying you. Seek urgent care for severe pelvic pain, fainting, heavy bleeding after a missed period, or symptoms that could suggest pregnancy complications. Bleeding after menopause also requires medical assessment.

Could pregnancy or another condition explain this missed period? Should I have tests for thyroid function or other causes? Which changes in bleeding should lead me to seek urgent help?