This is a non-interventional, retrospective, multicentre study involving women having had a breast cancer during their pregnancy, diagnosed between 2000 and 2014 (cases) and non-pregnant women having had a breast cancer between 2000 and 2009 (controls).

Investigators will explain the purpose of the study to the eligible patients, still alive, and will inform them verbally and in writing, using the information note, of their possibility of refusal. No information will be made for deceased patients.

The investigators will complete the case report forms on paper and then will send them by mail.

Inclusion Criteria:

• Women aged 18 or over

• Confirmed histological diagnosis of invasive breast cancer

• No known metastasis

• For the cases :

  • Patients pregnant at the time of the first diagnosis
  • 1st diagnosis between 2000 and 2014

• For the controls :

  • Patients not pregnant at the time of the first diagnosis
  • 1st diagnosis between 2000 and 2009

Exclusion Criteria:

• Patients who have undergone an induced abortion after the diagnosis of breast cancer
• Patients with a history of breast cancer

This study being retrospective, we will include all the subjects that meet our inclusion criteria over the period analyzed.