When you hear the word testosterone, you immediately think of men. Unknown to most people, women also produce the testosterone hormone but evidently in much lower amounts. Testosterone is the male hormone responsible for aggression and secondary male characteristics. When women have this hormone in higher levels, they usually have hirsutism or excessive facial hair, smaller breasts, and a protruding Adamâ€™s apple. There are actually women who are mistaken for men because they have more testosterone in their bodies. The imbalance of testosterone levels can either be an excessive increase or a excessive decrease in the amount of hormone.