BRCA1 and breast carcinoma: In the retrospective part of the study by Schrijver et al., a total of 5705 carriers of pV in BRCA1 and 3,521 carriers of pV in BRCA2 were found to have an increased risk of breast cancer as a result of taking oral contraceptives (BRCA1: HR 1.39; 95% CI 1.23–1.58; BRCA2: HR 1.52; 95% CI 1.28–1.81) (Schrijver et al. 2018).