A missed period doesn’t always mean pregnancy; several other factors can disrupt the menstrual cycle. Stress is one of the most common causes, affecting hormone levels and delaying ovulation. Sudden weight changes, excessive exercise, or poor nutrition can also impact your cycle. Hormonal imbalances such as thyroid disorders or polycystic ovary syndrome (PCOS) may lead to irregular or missed periods. Certain medications, birth control changes, and underlying health conditions can also play a role. In some cases, perimenopause or breastfeeding affects menstrual regularity. If missed periods persist or are accompanied by other symptoms, consulting a gynecologist is recommended.