Doctors said the three newborn girls and their mother are "feeling well." The babies, each weighing 1.7 kilograms (3.7 lbs), are currently in an incubator.
The mother, named Pamela, from the remote town of Leones, in central Argentina, had her first set of female triplets aged 15. She gave birth to her first child when she was only 14.
All her seven children, from three different fathers, were born prematurely. None of the fathers took responsibility for the children and Pamela had to leave school to look after her growing family.
Pamela's mother, Magdalena, 49, also a mother of eight children, said she tried to persuade her daughter to use contraception. However, doctors refused to allow the girl any family planning treatment as she was too young.
After the first triplets were born Pamela's family were given some land and a house. Meanwhile, Magdalena who works as a cleaner to help her daughter, said they might seek more assistance from the government.
"Pamela has only me. She is a good mother, although she is a girl herself," Magdalena said.
