According to Italian newspaper Il Gazzetino, she was rushed to the Bartolomeo Eustachio hospital in San Severino Marche by her fellow sisters and underwent an ultrasound, which revealed she was pregnant.
The nun, thought to be from Colombia, was immediately taken to the maternity ward, where her waters broke and she gave birth after a few hours of labour.
The newborn baby boy is reportedly in good health and will stay in hospital temporarily for medical checks.
The mother's convent is yet to issue a statement but the sisters have shown interest in taking charge of the baby, according to thelocal.it.
The case bears remarkable similarities to one a year ago, when a Salvadorean nun gave birth after also suffering from stomach cramps.
Roxana Rodriguez was taken from her convent to hospital Rieti, north-east of Rome, where she gave birth. Her fellow nuns were said to be "very surprised" by the arrival of the baby boy, who was named Francesco after the Pope.
