Study Links Planned C-Sections to Increased Childhood Cancer Risk

Recent research from Karolinska Institutet indicates that children delivered via planned cesarean sections (C-sections) may face a heightened risk of developing acute lymphoblastic leukemia (ALL) later in life. This finding, while noteworthy, is emphasized to maintain that the overall risk remains low.

The study, published in The International Journal of Cancer, analyzed data from nearly 2.5 million births in Sweden spanning two decades, from 1982 to 1989 and from 1999 to 2015. Out of this population, approximately 15.5%, or nearly 376,000 children, were delivered via C-section. Among these births, 1,495 children went on to develop leukemia.

Utilizing the Medical Birth Register, researchers categorized the C-sections into planned and emergency procedures. Findings revealed that children who developed leukemia were disproportionately represented in the planned C-section group. Specifically, the incidence of ALL was found to be 21% higher among those born through planned C-sections compared to those delivered vaginally.

Furthermore, the risk of the most prevalent form of ALL, B-cell acute lymphoblastic leukemia (B-ALL), was 29% greater in children born via planned C-sections. This increased risk persisted even after adjusting for various maternal and child-related factors. Notably, the elevated risk was more pronounced in male children and those at younger ages.

Despite these findings, researchers stress that the absolute risk remains low. In Sweden, approximately 50 to 70 children are diagnosed with B-ALL each year, translating to an increase of roughly one additional case associated with planned C-sections, according to the research team.

"While C-sections are crucial and can be life-saving in many cases, it is important to consider these findings when discussing non-medically indicated C-sections," stated Christina-Evmorfia Kampitsi, a researcher at the Institute of Environmental Medicine, Karolinska Institutet, and the lead author of the study.

The researchers propose several potential explanations for the association between planned C-sections and certain diseases, primarily focusing on immunological factors. They note that emergency C-sections typically begin with a vaginal delivery attempt, exposing the newborn to stress and vaginal bacteria, if applicable. In contrast, planned C-sections occur before natural labor begins, which may eliminate this exposure and stress, potentially contributing to the observed increased risk of ALL.

While some findings did not meet the statistical significance threshold, the researchers believe the results are significant enough to warrant attention. "Since ALL is relatively rare, a large number of C-sections would be required to observe statistically significant results. However, our findings align with previous studies and remain relevant even after accounting for various factors," they noted.

This study contributes to an evolving understanding of the potential long-term health implications associated with different modes of delivery and emphasizes the need for informed discussions regarding the necessity of planned C-sections.