Unintended pregnancy during the first year after breast cancer diagnosis.

Objectives: Young women experience high levels of anxiety and distress during cancer diagnosis and therapy, and it can be devastating to become pregnant in this vulnerable state. Pregnancy during cancer treatment is strongly discouraged, as radiotherapy and chemotherapy administered during the first trimester of pregnancy result in increased congenital malformations.

Methods: In this study, we analysed an unselected, consecutive cohort of young breast cancer (BC) patients with regard to unintended pregnancy during the first year after BC diagnosis. We analysed all patients who were ≤40 years of age at initial BC diagnosis (n = 100, mean age at diagnosis: 35.9 years), according to data from the Basel Breast Cancer Database. The frequency of unintended pregnancy was assessed, and particular attention was given to patients' obstetric and reproductive history.

Results: Forty-two percent of the cohort (mean age 36.5 years) were identified as not at risk of unintended pregnancy during the first year after BC diagnosis. However, 58% of the cohort (mean age 35.6 years) were using an ineffective contraceptive method and thus were at risk of unintended pregnancy. The rate of unintended pregnancy was 3.5% in this group (two patients). Oncologists should be aware that the use of reliable contraception should be discussed before starting, and also during, adjuvant therapy.

Conclusions: Oncologists should consider actively referring young BC patients to a gynaecologist to ensure proper contraceptive counselling.