After graduating with a degree in drawing from the Norwegian National Academy of Craft and Art Industry, Berggrav studied drawing and photography at Schule Reimann in Berlin in the early 1930s.
Back in Oslo, she opened her own photography studio, served as a scientific photographer and illustrator at the National Hospital, and worked as a press photographer for Arbeiderbladet. She also worked as the scientific photographer for Austrian physician and psychotherapist Wilhelm Reich when he lived in exile in Norway from 1934 to 1939.
When the Germans invaded Norway on 9 April, Berggrav followed the king and the government on their retreat north to Hamar and Elverum, then up the Gudbrandsdal valley and on to Molde. She accompanied the Norwegian central bank’s transport of gold bullion to Tromsø in the High Arctic, before witnessing the frontline action in Narvik, until she had to flee the country following Norway’s capitulation that June. She took photographs during the entire campaign, and although she reportedly lost most of them during the escape to the US, several of the pictures did end up in the Norwegian press agency NTB’s war archive.
During the war, Berggrav worked as a photographer at the Little Norway training camp in Canada, the Norwegian information centre in New York, and finally the Norwegian embassy in Washington, DC. For a while she also worked as an animator, photographer, and researcher at the Walt Disney Studios in Hollywood.
Berggrav remained in the US after the war and worked as a photographer for the United Nations from its founding in 1946 and until the early 1950s.