Cancer risk in children, adolescents, and young adults conceived by ART in 1983-2011

STUDY QUESTION: Do children, adolescents, and young adults born after ART, including IVF, ICSI and frozen-thawed embryo transfer (FET), have an increased risk of cancer compared with children born to subfertile couples not conceived by ART and children from the general population? SUMMARY ANSWER: After a median follow-up of 18 years, the overall cancer risk was not increased in children conceived by ART, but a slight risk increase was observed in children conceived after ICSI. WHAT IS KNOWN ALREADY: There is growing evidence that ART procedures could perturb epigenetic processes during the pre-implantation period and influence long-term health. Recent studies showed (non-)significantly increased cancer risks after ICSI and FET, but not after IVF. STUDY DESIGN, SIZE, DURATION: A nationwide historical cohort study with prospective follow-up was carried out, including all live-born offspring from women treated with ART between 1983 and 2011 and subfertile women not treated with ART in one of the 13 Dutch IVF clinics and two fertility centers. PARTICIPANTS/MATERIALS, SETTING, METHODS: Children were identified through the mothers' records in the Personal Records Database. Information on the conception method of each child was collected through the mother's medical record. In total, the cohort comprises 89 249 live-born children of subfertile couples, of whom 51 417 were conceived using ART and 37 832 were not (i.e. conceived naturally, through ovulation induction, or after IUI). Cancer incidence was ascertained through linkage with the Netherlands Cancer Registry for the period 1989-2019. Cancer risk in children conceived using ART was compared with risk in children born to subfertile couples but not conceived by ART (hazard ratio (HR)) and children from the general population (standardized incidence ratios (SIRs)). MAIN RESULTS AND THE ROLE OF CHANCE: