Which hormone is NOT associated with collagen production?

Testosterone is primarily recognized for its roles in muscle mass development, bone density, and the regulation of sex drive, rather than directly influencing collagen production. While collagen is an essential protein in maintaining skin integrity, strength, and elasticity, hormones like estrogen, growth hormone, and progesterone have more direct associations with collagen synthesis.

Estrogen, for instance, not only aids in maintaining skin elasticity but also promotes collagen production by increasing fibroblast activity in the skin. Growth hormone plays a vital role in stimulating the liver and other tissues to produce insulin-like growth factor, which is crucial for the growth and regeneration of tissues, including the stimulation of collagen synthesis. Progesterone, while primarily known for its functions in the reproductive system, can also have effects on skin and connective tissues, indirectly supporting collagen production.

Thus, testosterone is not primarily linked to collagen synthesis, making it the answer that best fits the question's requirement.