When Michelle Tatu got her first period, she was afraid she was dying. Terrified, she stuffed bits of cloth and cotton inside herself to try to stem the bleeding.

Too frightened to tell her parents what was happening, she kept quiet. She spent her school day terrified blood would leak out, exposing her to ridicule from her classmates.

“At first I was so scared, I didn’t know what it was, I thought I had hurt myself,” exaplains Tatu over the din of a women’s rights march in Kibera, her home and one of Kenya’s largest slums. The march has been organised by non-profit The Cup, which provides menstrual cups to girls like Tatu.

As the world marked Human rights day on 10 December 2016, residents of Kibera came together to use this day to raise awareness towards a particular issue - the rights of young women Photograph: Emma Nzioka

Today, little trace is left of that fear. Tatu is now 17 and uses a menstrual cup that she can wash regularly and use for up to ten years. “[Menstruation] happens to all girls, why would I be embarrassed?”

But Tatu’s initial experience is common across Kenya, and the rest of the continent. As many as one in 10 girls in sub-Saharan Africa are missing school during menstruation.

Just a decade ago, there was little discussion of the challenges girls in sub-Saharan Africa faced with their periods. In recent years, a groundswell of attention by non-profits, development organisations and governments means there is a growing consensus: girls should have access to the products they need without shame or secrecy.

“The time when a girl’s world is supposed to open up instead becomes a time when her opportunities are beginning to contract,” says Alison Nakamura Netter, chief communications and development officer for ZanaAfrica, which provides sanitary products and reproductive rights education in Kenya.

Marchers gave out flyers with information on how young women can get access to help and counselling if they become a victim of violence Photograph: Emma Nzioka

Helping girls is difficult when a dearth of research means there’s still so much we don’t know about how periods affect their educational and social outcomes. Luckily, emerging research is beginning to change that.

In Kenya, 65% of women and girls (pdf) are unable to afford sanitary pads. “When people earn less than two bucks a day, is a family going to [get] bread, milk and food, or a girl’s sanitary pads?” says Angela Lagat, chief brand marketing officer at ZanaAfrica.

The situation is so dire that in a 2015 study of 3000 Kenyan women, Dr Penelope Phillips-Howard found 1 in 10 15-year-old girls were having sex to get money to pay for sanitary ware.

17 year old Celine Awino was part of the march, organised by The Cup, a Swedish organisation Photograph: Emma Nzioka

Before Tatu started using a cup last year, she used rags and mattress stuffing when she couldn’t afford pads, causing infections and painful sores more than once.

Caro Muhonja, a 21-year-old Kibera resident walking by the march with her two daughters, says she often has to use cotton and scraps of fabric because sanitary products are too expensive. “They burn, they sting, they irritate my skin, and they leak and soil my clothes,” she says of the ad hoc alternatives.

The Kenyan government is considered a global leader on access to sanitary products. It repealed added tax on pads and tampons in 2004 to lower the price – a tax that still exists in the US – and since 2011, with the help of ZanaAfrica, the government has allocated money to distribute free pads to school girls.

But this programme hasn’t always been implemented well. Sometimes pads are stolen and or supplies run out. Also, it’s unclear whether the programme has improved school attendance in Kenya.

A number of women are unable to afford sanitary pads so are forced to use pieces of cloth or cotton wool which results in skin irritations Photograph: Emma Nzioka

“The need for products is unmet,” says Eunice Muthengi, lead researcher of a study on the effects of sanitary pad distribution and reproductive rights education on girls. “But we really don’t have enough evidence to show the impact of a lack of sanitary pads on absences or school performance.”

One problem may be that products alone aren’t enough. “While products and materials are essential, you can’t manage your period if you don’t understand what is happening to your body and don’t have basic information about reproductive health,” says Marni Sommer, an associate professor at Columbia University who studies adolescent health in sub-Saharan Africa.

During Muthengi’s preliminary research she found one girl who knew more about Ebola, of which there’s never been a case in Kenya, than she did about menstruation. Other girls in the same study thought women could only become pregnant by having sex during menstruation.

“Girls don’t talk about these issues, so I’m not sure if any other women face them,” says Muhonja about her own struggles.

Women and men from different parts of Kibera gathered at the DC camp in Kibera early morning and peacefully marched through the streets Photograph: Emma Nzioka

Access to sanitary products is of limited help if schools don’t have the supporting infrastructure, such as separate bathrooms for girls with doors and locks for privacy. In rural areas of Kenya, only 32% of schools (pdf) have a private place for girls to change their sanitary products. Many teachers are also uncomfortable talking about or teaching menstruation.

Only half of Kenyan girls (pdf) say they openly discuss menstruation at home presenting a missed opportunity for future education.

“Here’s this wonderful moment upon which a girl’s life changes that, although taboo, parents are probably more comfortable talking about than sex,” says Sommer. “Those conversations can open the door to communication so that they could eventually talk about more sensitive issues.”

The Kenyan government, with the support of Unicef, is developing national guidelines for menstrual hygiene in schools, including proper hand washing facilities and places to dispose of sanitary products, says Agnes Makanyi, water sanitation and hygiene specialist at Unicef in Kenya.

But perhaps most important is the emerging research. Muthengi’s study, in partnership with ZanaAfrica and the Bill and Melinda Gates Foundation, is the first of its kind in sub-Saharan Africa. ZanaAfrica will distribute a variety of sanitary products and will pilot Nia teen magazine , to teach girls about menstruation and reproductive health. The final study will provide insights into the individual and combined effects of sanitary pad distribution and reproductive health education on girls’ education and health.

A young woman on the march wears a Girl Power t-shirt Photograph: Emma Nzioka

“Funds are limited so we want to make sure we’re investing funds in what works, so that we’re getting the biggest bang for our buck,” says Muthengi.

The study will hopefully mean that all girls can laugh as much as Tatu did at the idea that a period is ever something to be embarrassed of. Or, as Netter says, “breaking the period taboo and making menstruation something that should be celebrated and not shamed”.

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