A practical guide to the signs of PCOS, which usually appear between the ages of 20 and 30 but can start earlier. The chapter covers ovulation problems, from irregular cycles to periods stopping altogether, and the visible effects of high androgen levels: excess hair growth (and the Ferriman-Gallwey scale used to measure it), acne and thinning scalp hair. It also looks at weight gain and insulin resistance, skin changes such as darkened patches and skin tags, and why pelvic pain is usually linked to related conditions like endometriosis rather than PCOS itself.