The report underlines the importance of hygiene and sanitation facilities in schools, particularly for girls, who are more likely to attend school and complete their education if these are in place.

For adolescent girls in particular, being able to change and dispose of sanitary pads and wash their hands in a single-sex space is crucial in encouraging them to attend school.

The report estimates that in 2016 355 million girls went to schools where they were unable to wash their hands after changing sanitary pads.

Thérèse Mahon, WaterAid regional programme manager for South Asia, said: “Providing better water, sanitation and hygiene services plays an important role in improving the quality of education for adolescent girls, so they can manage their periods safely and with dignity at school.”

A recent WaterAid and Unicef report showed that around one in three girls in South Asia are missing school days every month, in part because they have no privacy and are unable to wash their hands after changing sanitary towels or pads.

One of the sustainable development goals – the successor to the millennium development goals – is that everyone should have access to decent water and sanitation by 2030. This means that all settings, including households, schools, health care facilities and workplaces, should provide this – but many countries are are unlikely to reach these targets.