Hope Juarez is called a miracle baby for a reason. She was born with almost no blood. The baby was pale as a ghost when she was born via C-section at a hospital in Irvine, California, because 80 percent of her blood had drained out of her body as a result of fetal-maternal hemorrhage.

Fetal-maternal hemorrhage occurs in both normal pregnancies and pregnancies with trauma-related complications. It happens when the membrane that keeps the maternal and fetal circulations from getting direct contact with each other fails to act as barrier causing the fetal cells to come in contact and leak into the maternal circulation.

Marielle Nguyen, a neonatologist at the hospital where the miracle baby was born, said she did not know what caused the fetal-maternal hemorrhage. "We don't know what causes it. A lot of it is just it happens spontaneously," she said. "Sometimes the cause could be a motor vehicle accident, trauma, or where we have placental rupture, where the placenta suddenly just comes off the uterine wall." None of these happened to the baby's mom and so the reason behind the baby losing most of her blood is unknown.

Josh Juarez, the baby's father, said that no blood came out when the baby was pricked at her feet. Doctors also found that the baby's hemoglobin level was about 3.8 while normal babies often have between 10 and 15.

So-called ghost babies are rare because fetal-maternal hemorrhage can lead to the baby dying in the womb. Those who survive are also at risk of neurological damage. Hope was lucky because her mom, Jennifer Juarez, did something right away when she noticed the baby stopped kicking and suspected something was wrong.

"In Hope's case, her outcome was beautiful because it was the classic textbook case they tell you about," Nguyen said. "The mom knew right away that she had a clue something was wrong. She couldn't feel the baby move. And she came in right away and we delivered the baby. If we had waited any longer, the outcome would have been different."

Doctors are now monitoring Hope for any sign of delayed development but everything appears to be normal so far.