ESPE Yearbook of Paediatric Endocrinology

Cancer. 2021; 127: 1439–1447. https://pubmed.ncbi.nlm.nih.gov/33491215/

This nationwide, Finnish registry-based study identified a lower likelihood of primary pregnancy (relative risk =0.72; 95% CI, 0.64–0.80) in 1357 childhood cancer survivors (CCS) diagnosed in 1971-2012 and 6658 age-matched general population controls. However the risk of induced abortion was similar in both groups.

Parenthood is diminished in CCS, as a consequence of both impaired fertility and concern about their offspring’s health. Induced abortions in CCS have been evaluated in comparison to siblings and/or general population, with contrasting results, probably due to the age of the study population and cultural differences regarding induced abortion (1-3). Here, data from four Finnish registries for cancer, births, and induced abortions were merged to identify 420 primary pregnancies in CCSs and 2508 primary pregnancies in age-matched population controls. The risk of primary pregnancy was reduced in CCS compared to controls (relative risk =0.72; 95% CI, 0.64-0.80), whereas the risk of a primary pregnancy resulting in an induced abortion was similar in CCSs and controls, including when stratifying by decade of diagnosis and cancer treatment. These results suggest that female CCS who become pregnant are as willing as their peers to continue their pregnancy and become parents. The overall reduced probability of pregnancy highlights the persisting need for interventions to preserve fertility at the time of cancer diagnosis.

The registries used in this study lacked detailed information on cancer treatment (radiation dose and field, specific chemotherapeutic agents) and were based only on the first 4 months of therapy. For these reasons, the association between cancer therapies and the probability of pregnancy could not be completely defined. Moreover, social difficulties can influence the decision to terminate a pregnancy and data on socioeconomic status were not available for the majority of both CCSs and controls. Using the same approach, it would be useful to analyze frequency and outcome of pregnancy, in relation to long-term therapy, disease-related complications, education and socioeconomic status.

Reference: 1. Falck Winther J, Boice JD, Svendsen AL, Frederiksen K, Olsen JH. Induced abortions in Danish cancer survivors: a population-based cohort study. J Natl Cancer Inst. 2009; 101: 687–9.2. Hohmann C, Borgmann A, Keil T. Re: induced abortions in Danish cancer survivors: a population-based cohort study. J Natl Cancer Inst. 2011; 103: 698.3. Anderson R, Brewster D, Wood R, et al. The impact of cancer on subsequent chance of pregnancy: a population-based analysis. Hum Reprod. 2018; 33:1281–90.