Dellamonica was born as Madeleine Fortin in the ninth arrondissement of Paris, France, on 23 July 1912 as the daughter of Jean Fortin and Marie Moulinet. She attended secondary school at Cours Janné in Le Vésinet, and went on to study Egyptology at the École du Louvre.
Dellamonica married her husband, Rodolphe Charles Dellamonica, on 25 April 1933 in Le Vésinet. They were married for over 58 years until Rodolphe’s death on 7 January 1992 in Nice. In 2012, she celebrated her 100th birthday in Le Vésinet with two of her childhood friends.
Dellamonica published many works during her career, and collaborated on several others. These include:
As of October 2024, Dellamonica lives in Le Vésinet at the age of 112. Her sister, Suzanne Tunc, lived to be 103 years old, and was a doctor of law and theology.
Dellamonica is one of the oldest living people notable for reasons other than her longevity, having published many works on the last pharaohs and the lives of women in ancient Egypt.