Every year, 2 million girls give birth before the age of 15, according to the United Nations Population Fund. That's about 5,500 very young girls who become mothers each day — before their bodies are ready. Becoming a mother too young can involve huge health risks, including fistula (a hole between the vagina and the rectum caused by prolonged labor), and in some cases, even death. Research by the UNFPA shows that very young teenagers in low- and middle-income countries are twice as likely to develop fistulas and die during childbirth than older teens and women.Aside from the serious health problems they face during pregnancy and childbirth, once girls have their babies, many drop out of school, and suffer in silence. In fact, millions of child mothers remain invisible, excluded from national and global statistics, which deem the reproductive age of girls and women to be between 15 and 49 years old.This week, global leaders, civil society organizations, and nonprofit groups are gathering together for the Women Deliver conference, a chance to tackle some of the pressing issues that girls face in the modern world, including the plight of child mothers.Earlier this year, photographer and filmmaker, Pieter ten Hoopen, and I met with child mothers from around the world and asked them to share their stories. The results are moving, harrowing, insightful, and hopeful. These photographs will also be displayed around the world as part of Plan International and the UNFPA's #ChildMothers awareness initiative.Ahead, these girls share their powerful stories and hope for the future.Caption: Ana*, 15, lives with her daughter, Karen*, 4 months, parents, and two sisters in a violent neighborhood in a large city in Colombia.Editor's note: Sofia Klemming Nordenskiöld is a journalist and Plan International Sweden press officer. All photos and captions were provided by Plan International. *All names have been changed by Plan International for protection purposes.Correction: An earlier version of this slideshow misidentified the subjects of the photos in slide 13 and slide 16. Refinery29 regrets the errors.