The impact of combined oral contraception and hormone replacement therapy on breast cancer development

The assessment of breast cancer relative morbidity risk in women taking oral contraceptives (OC) or hormone replacement therapy (HRT)-currently known as menopausal hormone therapy-is still a challenge. The analysed groups of women vary widely depending on the type, route of application and doses of hormones, the duration of administration, and the time from therapy cessation. Moreover, the risk of breast cancer depends on the patient's genetic predisposition, and for this reason the analyses of OC and HRT should be performed separately in the group of healthy women, in BRCA1/2 mutation carriers, and in breast cancer survivors. This paper was aimed to analyse the safety of OC and HRT in three groups of women depending on the risk of breast cancer development (healthy women) or breast cancer recurrence (breast cancer survivors).