As your body goes through changes your skin can also be affected. For example, pregnancy and birth control can cause your skin to go through changes. During pregnancy your body is going through lots of changes. It causes the body to produce more melanin than usual. While pregnant you may experience dark spots around the chin, forehead, jawline, cheeks and nose. These changes are known as the mask of pregnancy. Of course every individual is different but for most this type of hyperpigmentation can last for the entire 9 months of pregnancy, unless the hormones return back to their normal levels.