As an engineer, I would argue that birth control's primary use is recreational.

Don't forget the secondary health benefits, such as reducing menstruary symptoms, which for some women is very uncomfortable.

That's quite often the primary, not the secondary. Protecting against unwanted pregnancy is a nice side-effect of the medicine prescribed to help control literally debilitating menstrual cycles.

Is a ski helmet recreational? Not directly; but it makes a recreational activity safer, so it provides indirect recreational value.

Whether birth control pills are used for recreational purposes is a question of semantics; they have no direct recreational use, but make indirectly support recreational activities.

I have had friends on "birth control" for acne, polycystic ovarian syndrome, migraines, endometriosis and a host of other non-child related issues.

Despite Rush Limbaugh claiming otherwise. https://en.wikipedia.org/wiki/Rush_Limbaugh%E2%80%93Sandra_F...