During pregnancy, a new vital organ is formed, the placenta, whose function is to protect the foetus from potentially harmful substances and ensure its safe development. The incidence of breast cancer during pregnancy is 19.2 cases per 100,000 pregnancies. It poses a major threat to both the foetus and the mother due to the limited range of therapies available, favouring the progression of the disease. Doxorubicin is a chemotherapy drug considered one of the safest, but several studies on placental trophoblasts have reported significant passage through the placenta. Consequently, adverse effects on the foetus have been observed, in some cases leading to foetal death.