This transition is a gradual process when symptoms ebb and flow, so it can be hard to recognise changes in your body. You may have begun perimenopause without even knowing it. Changes in your periods may be the first sign that you may be entering perimenopause. Your period can become lighter or heavier, briefer or longer, more frequent or more spaced out than usual. You can also experience other symptoms like hot flashes, night sweats, or changes in your skin & hair, your energy levels, mental health, sleep patterns and sexual desire.