Assessment of Birth Defects and Cancer Risk in Children Conceived via In Vitro Fertilization in the US
A cohort study of live births, birth defects and cancer from 1,000,639 children born to fertile women and 52,776 children conceived by IVF was followed for an average of 5.7 years. Using birth defects registries, cancer registries and the national IVF database, hazard ratios were calculated for birth defect and cancer associations in both fertile and IVF groups.
The hazard ratio for cancer risk among IVF children with a major birth defect was 6.9 ( 95% CI, 3.73-12.74) compared to the fertile group at 3.15 (95% CI, 2.40-4.14). This 2 fold increase in risk remained consistent when birth defects where categorised further, chromosomal vs non-chromosomal.
| Group | Non-chromosomal | Chromosomal |
| Fertile | 2.07 (95% CI, 1.47-2.91) | 15.45 (95% CI, 10.00-23.86) |
| IVF | 4.04 (95% CI, 1.86-8.77) | 38.91 (95% CI, 15.56-97.33) |
Hazard ratios for cancer risk among children born with a chromosomal and non-chromosomal defect
Interestingly the cancer risk for IVF children born without any major defect was NOT significantly increased when compared to children conceived naturally.
SUMMARY: IVF CANCER RISK IN CHILDREN
This latest study evaluating 52,776 children conceived by IVF, confirmed that the cancer risk for IVF children born without any major birth defect, is in fact identical to children conceived naturally. However, in IVF children with a birth defect, a 2-fold increase risk of cancer exists, compared to a matched child conceived naturally.
Limitations
- Unable to analyse specific birth defect and cancer combinations to further understand the link
- Average follow up period of only 5.8 years, where incidence of childhood cancer is low
Similar studies
Lupo P J, et al. (2019). Association between birth defects and cancer risk among children and adolescents in a population-based assessment of 10 million live births. https://doi.org/10.1001/jamaoncol.2019.1215
Carozza S E, et al. (2012). Are children with birth defects at higher risk of childhood cancers? https://dx.doi.org/10.1093/aje/kwr470
