The girl, known as Dafne, delivered by C-section on Jan. 27 a baby girl who weighed 5.7 pounds. The baby was delivered in a hospital, but Dafne hadn't received any previous medical treatment for her pregnancy.
"It is dismaying that a young girl became pregnant. You shouldn't be pregnant at that age," said Enrique Rabago, director of the Occidente General Hospital in Zapopan, where the baby was born.
Rabago told reporters a C-section was done because it was safer for the mother and baby.
Mother and child were in good condition, AFP reported, and will have extensive follow-up care because of the mother's age.
State prosecutors told AFP Dafne said she has consensual sex and was in a relationship with the father, but officials describe it as a case of rape or child abuse.
Dafne's mother said the girl became pregnant at age eight and the father is 17.
AFP reports that the father offered to live with Dafne when he learned of the pregnancy, but she refused and he ran away.
A source told AFP Dafne is from a village 30 kilometres from Guadalajara and is one of 11 siblings.
A reproductive specialist told AFP that pregnancies in girls between 10 and 12 years old are commonly due to rape, adding physical immaturity puts girls at higher risk.