[1] Stoltenberg began her career with an internship in the Helgeland region before working as a registrar at Rikshospitalet University Hospital, and later in casualty departments in both Aurskog-Høland and Oslo.

For her doctoral thesis, Stoltenberg studied infant death, social inequality and consanguineous marriage in immigrant groups.

[8] In the preparations for the Global Health Summit hosted by the European Commission and the G20 in May 2021, she was a member of the event's High Level Scientific Panel.

[9] In April 2023, it was announced that Stoltenberg would become the new director of the Norwegian Research Centre (NORCE) and would assume office on 1 October.

[10] Stoltenberg played an important role in uncovering that a medical article submitted by Jon Sudbø to the Lancet was an academic fraud.