What primarily causes the differences in male and female sexual hair patterns?

The primary factors influencing the differences in male and female sexual hair patterns are largely attributed to the concentration of circulating androgens. Androgens, such as testosterone and its derivatives, play a crucial role in the development of secondary sexual characteristics, including hair growth patterns. In males, higher levels of androgens lead to a greater density of terminal hair in areas such as the face, chest, and back, which are typical male patterns.

In contrast, females generally have lower levels of androgens, resulting in softer and less dense hair growth. The androgenic influence on hair follicles shapes not only the quantity of hair but also the texture and distribution, leading to distinct male and female patterns of hair growth.

While other factors like genetic predisposition and hormonal influences do play roles in hair growth, the primary driving force behind the observable differences between male and female hair patterns is indeed the varying concentrations of circulating androgens.