The chemistry, biochemistry, and physiological activity of steroids are under intense study in light of the great importance of steroids in medicine, veterinary science, and animal husbandry. In industry, chemical and microbiological methods have been introduced for the partial synthesis of steroid hormones from available raw materials (sterols, bile acids, saponins), and in the 1960’s and 1970’s methods have been introduced for complete chemical synthesis from the simplest starting materials. The synthesis of “artificial” steroid hormones with specialized physiological effects (contraceptive, anabolic), in particular, fluorine-containing and nitrogen-containing analogs, is acquiring increasing importance.
A larger study with longer follow-up concluded that "use of DMPA during pregnancy or breastfeeding does not adversely affect the long-term growth and development of children". This study also noted that "children with DMPA exposure during pregnancy and lactation had an increased risk of suboptimal growth in height," but that "after adjustment for socioeconomic factors by multiple logistic regression, there was no increased risk of impaired growth among the DMPA-exposed children." The study also noted that effects of DMPA exposure on puberty require further study, as so few children over the age of 10 were observed. 
To strengthen the anabolic properties of testosterone, more than 100 synthetic steroid derivatives have been described for human purposes. The anabolic effect promotes protein synthesis, muscle growth and erythropoiesis. In clinical practice, substances with anabolic effect are needed to overcome various catabolic states. However, none of these compounds are devoid of androgenicity. Androgenic and anabolic properties of anabolic steroids cannot be totally separated. Therefore, it is more appropriate to use the term anabolic androgenic steroids (AAS).