Cancer in women or men during reproductive life raises fears and dilemmas regarding the ability to have a healthy child. Chemotherapy and radiotherapy increase genetic defects in germ cells, depending on the agent used and the stage of gamete maturation. No increase in miscarriage or congenital malformation rates is detected among children born years post-cancer treatment. However, when pregnancy occurred shortly after treatment, increased abortion and malformation risk was reported. Until more data are available, monitoring of chromosomal aberrations and birth defects is recommended. Complexity of cancer treatment is significantly amplified in women exposed to chemotherapy during pregnancy due to concerns regarding direct maternal risks caused by treatment and risk to the developing embryo-fetus. The potential teratogenic effect of cancer treatment depends upon the developmental stage of the fetus at exposure and on drugs used. During the first trimester, abortion and malformation rates are increased, while second- and third-trimester chemotherapy may increase the risk of stillbirth, fetal growth restriction, and premature birth. Maternal myelosuppression increases bleeding and infection tendency, which can harm the fetus. A multidisciplinary team alerted to possible consequences of cancer treatment on pregnancy outcome should provide the optimal treatment options for these patients.