[jay_neyer]

Tampons would have a high barter utility in a doomsday scenario. Alcohol and cigarettes would be in high demand too, I would imagine. Just think of household items people use on a daily/weekly/monthly basis that they couldnt live without.

[nosuchthing]

Tampons would eventually be phased out with reusable fabric or a diva cup like device (silicone reservoir).

[Mz]

Not only that, but if the body weight of a woman (particularly her fat reserves) drops too low, her periods become sporadic. So if women are starving, periods become less of an issue. Something about evolution designing for not getting women pregnant when they don't have the resources to feed themselves, much less nurture an infant. Mother Nature is weird like that.