Recent childbirth is an adverse prognostic factor in breast cancer and melanoma, but not in Hodgkin lymphoma

Melanoma and breast cancer prognosis are adversely affected by recent gestation and childbirth in a way that is not due to stage of the cancer, but rather to inherent biological properties of the tumours. Possible biological mechanisms include immunosuppression (melanoma), the hormonal milieu in gestation and a tumour promoting microenvironment post-partum (breast cancer).