What sex are you? If you are a man it can be as simple as the pattern of your body hair changing. It does this throughout your life, but particularly in your thirties. Emerging hair can often grow inwards, causing spots. Using a stiff back brush in the shower can help. If you are a woman (I'm sorry, the name Lolly could be either!) then the answer is probably hormonal. Key suspects are the pill, pregnancy, ovarian cysts ... if you are at all concerned see your doctor.