Joint effects of IVF and cancer history on birth outcomes

To examine how live birth rates, preterm birth, and major birth defects are affected by parental cancer history and conception method.

IVF births were identified by linking the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System to birth certificates in three States. For each IVF-conceived birth, the subsequent 10 naturally conceived births (from birth certificates) created the comparison group. Parental cancer history was identified by linkage to state cancer registries. Preterm birth (PTB) was defined from birth certificates; birth defects (BD) from state BD registries. Adjusted odds ratios (aOR) and 95% confidence intervals (CI) for PTB and BDs were calculated with logistic regression.

Overall, 30.5% of female cancer survivors who underwent IVF had a live birth. Of 814,658 total births, 9.1% were PT and 4.4% had BDs. IVF was associated with increased risk of PTB and major BDs regardless of parental cancer history. Maternal, but not paternal, cancer history was associated with an increased risk of PTB. No increase in BDs was observed with parental cancer history alone. Risks of both PTB and BDs were highest among multiple births.

IVF use was associated with increased risk of PTB and major BDs. Parental cancer history did not elevate the risk of BDs, which remains low. Based on these data, cancer survivors attempting to conceive with or without IVF can be counseled that the magnitude of risk for PTB and major BD was similar for cancer survivors compared with those who conceive without a parental cancer history.