Transdermal patches (adhesive patches placed on the skin) may also be used to deliver a steady dose through the skin and into the bloodstream. Testosterone-containing creams and gels that are applied daily to the skin are also available, but absorption is inefficient (roughly 10%, varying between individuals) and these treatments tend to be more expensive. Individuals who are especially physically active and/or bathe often may not be good candidates, since the medication can be washed off and may take up to six hours to be fully absorbed. There is also the risk that an intimate partner or child may come in contact with the application site and inadvertently dose himself or herself; children and women are highly sensitive to testosterone and can suffer unintended masculinization and health effects, even from small doses. Injection is the most common method used by individuals administering AAS for non-medical purposes. 
The differences between female hormones and male hormones may not be as specific as you might think. The definition of a hormone is a chemical substance produced by an endocrine gland that has a specific effect on the activities of other organs in the body. The major female and male hormones can be classified as estrogens or androgens. Both classes of male and female hormones are present in both males and females alike, but in vastly different amounts. Most men produce 6-8 mg of the male hormone testosterone (an androgen) per day, compared to most women who produce mg daily. Female hormones, estrogens, are also present in both sexes, but in larger amounts for women.
Testosterone is a hormone that is produced in large amounts by males (and a little bit in females), in the testes and adrenal glands. High testosterone levels are associated with sexual performance, reproductive function, muscle mass, hair growth, aggressive, competitive behaviors, and other such manly things. Testosterone levels tend to peak at the age of 40, and slowly decline from there. Luckily, there are many things you can do to increase testosterone, so if you feel like your T levels could use a boost, you've come to the right place.