UGANDA (REUTERS) - A group of entrepreneurs in Uganda are on a mission to keep girls in school by making cheap sanitary towels from sugarcane by-products.

One in ten girls in sub-Saharan Africa skip school during their menstrual cycle, meaning they miss up to 20 per cent of the school year.

Most don't have the money to buy sanitary pads.

Some even end up using unhygenic rags, while others drop out of school altogether.

"Many girls cannot afford the sanitary pads on the market. When you go to schools you will be surprised to know that some will miss school because they are going through their menstrual periods, the four days of their menstrual periods, they do not have the right materials to use, they are so embarrassed in public because they will stain their dresses." said Lydia Asiimwe, Co-founder of EcoSmart Pads.

Sugarcane was chosen because it's cheap and provides an absorbent fibre when processed.

The company is working with technicians at Uganda's Industrial Research Institute in Kampala.

"You have the sugarcane and the water that is already steamed coming in here, so what you are doing is boiling the sugarcane residue, mainly to remove the sugar content and to soften it." said Noel Aryanyijuka, Chief Executive, EcoSmart Pads.

UN children's agency UNICEF says keeping girls in school is one of the most effective strategies to combat child marriage. Providing them with these sanitary pads encourages them to stay in education.