Girls on their menstrual period are ostracised and banished from the society

Kamala believes that if she enters the house while she's menstruating, the people and animals will get sick. The gods will be angry and she'll bring a curse onto the house. She's also been told her hands will curl up and become deformed.

"I'm scared mostly of snakes and of men," she says through translator, Pragya Lamsal of Water Aid. Kamala has heard stories of girls being sexually assaulted when they're alone in their sheds.

Her shed is shocking. It looks more like a cage with wooden bars crisscrossed over the top and sides.

Popularly known as Chhaupadi, it is a social tradition in the western part of Nepal for Hindu women which prohibits a woman from participating in normal family activities during menstruation because they are considered impure.

The women are kept out of the house and have to live in a shed. This lasts between ten to eleven days when an adolescent girl has her first period; thereafter, the duration is between four and seven days each month.

During this time, women are forbidden to touch men or even to enter the courtyard of their own homes. They are barred from consuming milk, yogurt, butter, meat, and other nutritious foods, for fear they will forever mar those goods.

The women must survive on a diet of dry foods, salt, and rice. They cannot use warm blankets, and are allowed only a small rug. They are also restricted from going to school or performing their daily functions like taking a bath, forced to stay in the conditions of the shed.

Ancient Hindu scriptures say women are highly infectious during their periods, that "all her body is so weak that viruses come out of her mouth and her limbs," says Mukunda Aryal, who has studied Hindu culture for 40 years.

In Hinduism, there was once a king of the gods, who reigned above others. This god, called Indra, committed a horrible sin. And to atone for it, he created menstruation.

Now each month, women suffer for this god's sin. They're impure, dirty.

There's even an expression in Nepal that women say when they're on their periods: "I am now untouchable."

But although the country's supreme court banned practising chaupadi in 2005, the custom dies hard. It remains firmly rooted in many villages, especially in remote hill areas. A 2011 report estimated that 95 percent of women in Nepal still follow it.