These steroids can cause bad acne and fluid retention. Long-term use can stop the body from making testosterone. In men, this causes smaller testicles, lower sperm counts, infertility, and breast growth. Women may have male-pattern baldness, facial hair growth, periods that change or stop, and a deeper voice. Teens who use them might stunt their bone growth and height. High doses can lead to extreme mood swings, anger, and aggression called "roid rage."