European Journal of Cancer (Oxford, England : 1990), 215, 115168, 2024
Maternal use of hormonal contraception and risk of childhood leukemia: A Scandinavian population-based cohort study
Caroline H Hemmingsen, Susanne K Kjaer, Sarah Hjorth
Ulrika Nörby, Anton Pottegård, Justine Bénévent, Kjeld Schmiegelow, Charlotte Wessel Skovlund, Maarit K Leinonen, Hedvig Nordeng, Lina Steinrud Mørch, Marie Hargreave, Anne Broe
Virus, Lifestyle and Genes, Danish Cancer Institute, Copenhagen, Denmark; Department of Gynaecology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark. Electronic address: susanne@...
Maternal hormonal contraception use has been associated with childhood leukemia risk. However, studies are few and often based on self-reported information.
Methods
Using registry data from Denmark, Norway, and Sweden, we identified 3,183,316 children (born 1996-2018) and followed them from birth until leukemia diagnosis, censoring (death, emigration, other cancer, 20th birthday) or study closure (December 31st, 2017, 2018 or 2020). We estimated hazard ratios (HRs) and 95 % confidence intervals (CIs) for childhood leukemia (any, lymphoid and non-lymphoid) associated with maternal recent use (≤ 3 months before or during pregnancy) or previous use (before recent use) of hormonal contraception overall and by type, compared to no use.
Results
During 29,455,528 person-years, 1701 children developed leukemia (no use: 518, previous use: 974, recent use: 209). Maternal recent use of hormonal contraception was associated with an increased leukemia risk in children (HR 1.22, 95 % CI 1.04-1.44; incidence rate per 1,000,000 person-years [IR] 65), compared to no use (IR 53). The association was strongest for non-lymphoid leukemia (HR 1.69, 95 % CI 1.20-2.37) and mainly driven by the oral combined products, both for any leukemia (HR 1.29, 95 % CI 1.05-1.59) and non-lymphoid leukemia (HR 1.75, 95 % CI 1.17-2.62). Additionally, non-lymphoid leukemia was associated with recent use of the non-oral progestin-only products (HR 2.10, 95 % CI 1.28-3.44).
Conclusions
Although the absolute risk was low, maternal hormonal contraception use up to or during pregnancy was associated with an increased childhood leukemia risk, particularly non-lymphoid leukemia, and mainly driven by oral combined and non-oral progestin-only products.
maternal hormonal contraception childhood leukemia risk, oral combined contraceptive pregnancy childhood cancer Scandinavian cohort, hormonal contraception periconceptional exposure childhood leukemia, Hemmingsen Mørch contraception leukemia Scandinavian registry, progestin-only contraceptive non-lymphoid leukemia offspring risk, ethinylestradiol progestin preconception childhood leukemia population cohort, maternal contraceptive use before pregnancy cancer risk children, combined oral contraceptive periconceptional childhood acute leukemia, hormonal contraception pregnancy non-lymphoid lymphoid leukemia offspring, Scandinavian population cohort registry study contraceptive safety childhood cancer
PMID 39667251 39667251 DOI 10.1016/j.ejca.2024.115168 10.1016/j.ejca.2024.115168
Cite this article
Hemmingsen, C. H., Kjaer, S. K., Hjorth, S., Nörby, U., Broe, A., Pottegård, A., Bénévent, J., Schmiegelow, K., Skovlund, C. W., Leinonen, M. K., Nordeng, H., Mørch, L. S., & Hargreave, M. (2025). Maternal use of hormonal contraception and risk of childhood leukemia: A Scandinavian population-based cohort study. European journal of cancer (Oxford, England : 1990), 215, 115168. https://doi.org/10.1016/j.ejca.2024.115168
Hemmingsen CH, Kjaer SK, Hjorth S, Nörby U, Broe A, Pottegård A, et al. Maternal use of hormonal contraception and risk of childhood leukemia: A Scandinavian population-based cohort study. Eur J Cancer. 2025;215:115168. doi:10.1016/j.ejca.2024.115168
Hemmingsen, C. H., et al. "Maternal use of hormonal contraception and risk of childhood leukemia: A Scandinavian population-based cohort study." European journal of cancer (Oxford, England : 1990), vol. 215, 2025, pp. 115168.
Keywords
Contraceptives, Oral, Hormonal
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