What should you know about missing periods for a month?

Missing a period for a month can happen for many reasons, including pregnancy, stress, illness, weight change, hormonal contraception, or a changing menstrual pattern. A single late or absent period is often temporary, but it is worth checking pregnancy if it is possible and recording what happens next.

The menstrual cycle can shift after emotional stress, disrupted sleep, travel, intense exercise, an infection, or a significant change in eating or body weight. Starting, stopping, or missing hormonal contraception can also alter bleeding. Pregnancy is another possibility, even when cycles have previously been predictable; a home pregnancy test can help clarify this.

If missed or widely spaced periods keep returning, a clinician may assess thyroid function, prolactin, ovarian hormone patterns, or conditions such as polycystic ovary syndrome. In the years when menstrual cycles naturally become less predictable, perimenopause can also explain changing timing. The pattern over several cycles, along with symptoms such as acne, increased facial hair, hot flushes, nipple discharge, or pelvic pain, gives useful context.

If pregnancy is possible, take a home pregnancy test according to its instructions. If the result is negative but bleeding does not start, repeat the test later or arrange a clinical assessment, particularly if your cycles are usually regular. Note the first day of your last period, any contraception changes, medicines, recent illness, stress, exercise changes, and new symptoms.

Avoid taking hormones or products marketed to bring on a period without medical guidance. Arrange a routine appointment if missed periods recur, your usual cycle pattern changes noticeably, or you have symptoms suggesting a hormonal condition.

Seek urgent medical help for severe or one-sided lower abdominal pain, fainting, marked dizziness, shoulder-tip pain, or heavy bleeding, especially if pregnancy is possible. These symptoms can need prompt assessment.

Contact a clinician soon for a positive pregnancy test with pain or bleeding, new nipple discharge, severe headaches or vision changes, or rapidly worsening pelvic symptoms. Otherwise, a routine review can help identify the reason when the change persists or repeats.

You could ask: What causes fit my cycle history and symptoms? Should I take or repeat a pregnancy test? Could my contraception, medicines, thyroid, or polycystic ovary syndrome affect bleeding? What examination or tests are appropriate if my period remains absent?