Fetal outcome after prenatal exposure to chemotherapy and mechanisms of teratogenicity compared to alcohol and smoking.

Introduction: The treatment of cancer during pregnancy is challenging because of the involvement of two individuals and the necessity of a multidisciplinary approach. An important concern is the potential impact of chemotherapy on the developing fetus.

Areas Covered: The authors review the available literature on neonatal and long-term outcome of children prenatally exposed to chemotherapy. Chemotherapy administered during first trimester of pregnancy results in increased congenital malformations (7.5 - 17% compared to 4.1 - 6.9% background risk), whereas normal rates are found during second or third trimester. Intrauterine growth restriction is seen in 7 - 21% (compared to 10%), but children develop normal weight and height on the long term. Children are born preterm in 67.1%, compared to 4% in general population. Normal intelligence, attention, memory and behavior are reported, although intelligence tends to decrease with prematurity. Global heart function remains normal, although small differences are seen in ejection fraction, fractional shortening and some diastolic parameters. No secondary cancers or fertility problems are encountered, but follow up periods are limited.

Expert Opinion: Most evidence is based on retrospective studies with small samples and limited follow up periods, methodology and lack of control groups. A large prospective case-control study with long-term follow up is needed in which confounding factors are well considered.