Clinical Corner - February 2023

Since a variety of cancers occur in women during pregnancy, will the in utero exposure to maternal cancer and cancer treatment influence the unborn child's short- and long-term health and development? A recent study in Denmark investigated outcomes in children exposed to maternal cancer in utero between January 1978 and December 2018. Exposure was defined as maternal cancer diagnosis during pregnancy as well as exposure to chemotherapy in utero and identified in the National Health Registers.

Overall mortality, somatic diagnoses, and psychiatric diagnoses were assessed and follow-up started at birth and extended until the end of 2018. Of 2,526,163 liveborn children, 690 (0.03%) were exposed to maternal cancer in utero. Compared with unexposed fetuses, children exposed in utero had no higher overall mortality, nor increased risk of congenital malformations, somatic or psychiatric disease.

During the period 2002-2018, of 378 (0.03%) children exposed to cancer in utero, 42 (12.5%) were exposed to chemotherapy and had no increase of somatic diseases nor congenital malformations when compared with in utero exposure to maternal cancer without chemotherapy. Overall, findings did not indicate excess risk of mortality or severe morbidity among children exposed to cancer in utero. Fetal exposure to chemotherapy was not associated with adverse health outcomes in childhood.

Again, we see the power of the registry and the importance of capturing data relating to in-utero malignancy.