| Cycle timing | Cycles vary, and one unusual cycle can happen with stress, illness, travel, training changes, contraception changes, or breastfeeding. | No period for 3 months without an obvious reason, repeated cycles far outside your usual pattern, bleeding too often, or pregnancy possibility. |
| Bleeding length | Bleeding for several days can be part of a normal cycle. | Bleeding that lasts more than 7 days, returns quickly, or repeatedly disrupts work, school, sleep, exercise, caregiving, or sex. |
| Bleeding amount | Flow often changes across the period, with heavier and lighter days. | Soaking through products often, needing double protection, passing large clots, leaking overnight, or feeling weak, dizzy, or short of breath. |
| Spotting or bleeding between periods | Light spotting can occur for some people, especially with contraception changes. | Bleeding after sex, bleeding after menopause, repeated bleeding between periods, or spotting with pain, discharge, fever, or pregnancy concern. |
| Pain | Mild cramps that respond to ordinary self-care can happen. | Severe, worsening, one-sided, deep-with-sex, bowel/bladder-linked, fever-linked, or life-disrupting pain. |