It's hard to imagine this: children married before their teenage years. And when little girls get pregnant, having a baby will put their lives on the line.
One in every seven girls in the developing world are forced to marry before the age of 15. In Afghanistan, 57 percent of marriages involve child brides.
Miriam was married at 13. Her family received $2,000 for the marriage, the price of two cows. The younger the bride, the higher the price since virginity is prized in Afghanistan.
Miriam once dreamed of becoming a teacher, but was pulled out of school by her family before completing fifth grade.
"My wish," she said, "was to go to school and I didn't want to get married at all."
PHOTOS: Miriam and Other Child Brides
When we visited Miriam, she was 15 and seven months pregnant. Her mother-in-law told us she took Miriam to visit a clinic because "the age is not proper for delivery."
Miriam is less than five feet tall and weighs about 90 pounds, nearly the same weight as an average 10-year old American girl.
With her narrow hips and undeveloped body, she is in the danger zone and faces a risk of bleeding and infection after delivery.
Girls under the age of 15 are five times more likely to die in childbirth than young women in their twenties.
"Many of these girls end up in a marriage when their pelvises aren't fully formed , so they're much more likely to end up having obstructed labor and, in many cases, dying," said Nicholas Kristof, a columnist for The New York Times who has written extensively on issues facing the developing world.
But the girls' deaths are preventable.
"We know exactly how to save these lives. It's not that we need some kind of new technological breakthrough. The question is, are we willing to make those lives a priority?" he said.
By law, getting married before the age of 16 is prohibited. But it's not easy to break centuries of tribal custom, customs that can also keep pregnant women from receiving the care they need.
"There are enormous cultural impediments and one of the most frustrating things to me is the notion in a number of conservative Muslim countries that if a man is not there, if her husband is not there, then she can't be taken to a hospital to give birth. He has to give his permission," Kristof said.
Every two hours a woman dies in Afghanistan from pregnancy complications. They travel hours over rough, stony roads to reach the most basic of medical care. Many of them die before reaching it. But there are simple things that could save lives.
"The presence of some transportation to manage rudimentary roads, the presence of personnel trained in recognizing common complications," said Dr Sandra McCalla, clinical director of obstetrics for Maimonides Medical Center in New York.
More than 30 percent of women in the world still give birth without a skilled medical attendant. If a mother is alone and undergoing a hemorrhage, she will die. Most women still give birth at home partly because of tradition, but also because they are too poor to pay for a birth in a clinic.