KATHMANDU, Nepal — Parbati Bogati knew what to do when her period came.

Ms. Bogati, 21, sequestered herself in an abandoned house, in keeping with a centuries-old taboo that declares menstruating women impure, officials from her area in rural western Nepal said.

As the temperature dropped below freezing on Wednesday evening, she tried to keep warm, apparently burning wood and clothing.

By the next morning, her legs were charred and she was dead.

“It seems she also died from suffocation,” said Lal Bahadur Dhami, the deputy superintendent of the area’s police. At least three other people died this year while following the same superstition.

The taboo, which has its roots in Hinduism, is called chhaupadi, from the Nepali words meaning someone who bears an impurity. During women’s periods, it bars them from touching neighbors’ food or entering temples. They cannot use communal water sources or kitchen utensils. It is considered bad luck to touch them.