Ghanian school girls are facing a new obstacle on their way to school - a local river god has banned them from crossing the river while menstruating or on Tuesdays.

The BBC reports the ban has outraged children's activists, as it prevents many from being able to cross the river to get to school.

The ban applies to part of the River Ofin, which forms a boundary between the Ashanti and Central regions.

Students in the Upper Denkyira East district could miss out on their education due, as the ban prevents them from crossing the river to get to school.

Central Region Minister Kwamena Duncan has indicated he will work with the Ashanti regional minister to find a solution to the ban.

Sub-Saharan Africa is already having problems keeping students in school during menstruation, as a lack of access to sanitary products makes attending school during a period difficult.

Unicef's menstrual hygiene ambassador Shamima Muslim Alhassan was outraged by the ban, saying it violated students right to an education.

"It seems the gods are really powerful aren't they?" she told the BBC.

"Sometimes I think that we need to ask for some form of accountability from these gods, who continue to bar a lot of things from happening, to account for how they have used the tremendous power that we have given them."

The United Nations Educational, Scientific and Cultural Organisation (UNESCO) estimates one in 10 girls in the area do not attend school due to menstruation.

A 2016 report by the World Bank also found 11.5m people in Ghana lacked the proper access to hygiene and sanitation facilities needed for menstruation.

Newshub.