Assessment of Birth Defects and Cancer Risk in Children Conceived via In Vitro Fertilization in the US.

Area of Science:

• Reproductive Medicine
• Pediatric Oncology
• Medical Genetics

Background:

• Birth defects are associated with an increased risk of childhood cancer.
• This association has not been previously studied in children conceived through in vitro fertilization (IVF).

Purpose of the Study:

• To compare the risk of cancer in children with birth defects conceived via IVF versus those conceived naturally.
• To determine if the birth defect-cancer association is amplified in IVF-conceived children.

Main Methods:

• A cohort study analyzed live births, birth defects, and cancer diagnoses in four US states (2004-2016).
• Included over 1 million naturally conceived children and over 52,000 IVF-conceived children.
• Used Cox proportional hazards regression to analyze cancer risk, adjusting for birth defects.

Main Results:

• Children with major birth defects had a higher cancer risk: HR 3.15 (naturally conceived) and HR 6.90 (IVF-conceived).
• The risk was significantly higher for IVF-conceived children with major nonchromosomal defects (HR 4.04 vs. 2.07) and chromosomal defects (HR 38.91 vs. 15.45).
• IVF-conceived children with birth defects showed a substantially greater cancer risk compared to naturally conceived children with similar defects.

Conclusions:

• Children conceived via IVF with birth defects have a significantly elevated risk of developing cancer compared to naturally conceived children.
• Findings suggest enhanced surveillance for cancer in IVF-conceived children diagnosed with congenital anomalies.
• Further research is warranted to understand the underlying mechanisms driving this increased risk.