Back in 1939, a little girl named Lina Medina gave birth to a healthy baby boy. She was only five-years-old.

This story is truly a medical marvel — one that is surely hard to believe.

Lina lived in a small Peruvian village located 7,400 feet up in the mountains — the nation’s poorest region.

The girl’s parents initially thought their daughter was suffering from a massive abdominal tumor, but after being examined by doctors in Pisco, Peru, they discovered she was eight-months pregnant. Dr. Gerardo Lozada found that Lina’s mammary glands and sexual organs were fully developed.

When her parents were questioned about the pregnancy, Lina’s mother informed the doctor that she had been having a period since the age of three. However, upon further examination, Dr. Lozada realized her menstruation began at eight months.

On Mother’s Day, Lina gave birth to a six pound boy, whom she named Gerardo (after the doctor who diagnosed her).

Police arrested Lina’s father on suspicions of incest and rape, but he was later released due to lack of evidence. The identity of Gerardo’s father was never determined.

Throughout the years, many people have called her story a complete hoax, however, X-rays, photos, and doctors’ documentation are proof that this really did happen. We can definitely understand the hesitation because we cannot believe how she was able to carry her baby full term at such a young age.

Her child grew up thinking that his mother was his sister, though when he was 10-years-old her real identity was revealed.

Gerardo led a healthy life until 1979, when he died from bone marrow disease at the age of 40.