More than two billion people have it, yet much of the world is ashamed to talk about it. The Stream tackles the mystery of menstruation.

The natural biological process that keeps the human race going is basic science and essential knowledge. But many are not quite sure what it involves. In the best cases, confusion about periods can cause embarrassment and, in the worst cases, create harmful conditions for girls and women.

The menstrual cycle is how the female body prepares for pregnancy. Hormones cause extra blood and tissue to line the uterus or womb, which is where a fertilised egg can attach and grow. An ovary releases an egg each month, and if it is not fertilised, the body expels the extra blood and tissue and remnants of an egg. The cycle is not just the period, it’s the daily hormonal changes the can cause symptoms like headaches and cramps.

Nearly half the world’s population spends about 40 reproductive years going through this.

People do not always get this biology lesson, however. Myths and misperceptions are often presented as fact, and religious and cultural beliefs can make menstruation taboo and a source of shame.

Having access to hygienic products and facilities can make the experience easier. Without them, a period can be humiliating and disabling, keeping girls, women and the countries they live in from fulfilling their social and economic potential.

Development experts, for example, say a lack of private bathrooms in the world's poorest countries contribute to girls dropping out of school after they get their period. In Nepal last month, a teenager died in a menstrual hut, where she was secluded because of a tradition in her community. And in the UK and US, expensive period products and few public facilities prevent low-income and homeless women from being clean and healthy.

Despite the taboo, menstruation has become a trendy topic. Hashtag movements like #MenstruationMatters are making waves, and one of India’s most popular actors is starring in an upcoming movie about the real-life “Menstruation Man” who pioneered the design for low-cost, easy-to-manufacture pads. Efforts by artists, social entrepreneurs and health and women’s advocates are helping to normalise the unmentionable. And on Thursday, four of them will join The Stream to answer our community’s questions about the female body, discuss society’s responses to it and explore what we can do to support women and girls.

In this episode of The Stream, we speak with:

Dr. Amr Madkour @GW_mfa
Assistant Professor of Obstetrics & Gynecology

Sabrina Rubli @sabrinarubli
Chief Executive Officer, Femme International

Pablo Freund @pablofreund
Co-founder & Chief Operating Officer, Be Girl

Poulomi Basu @poulomibasu
New media practitioner, storyteller and activist

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