Does In Vitro Fertilization (IVF) increase the risk of breast cancer?

Does In Vitro Fertilization (IVF) Increase the Risk of Breast Cancer?

Based on the available evidence, IVF does not appear to increase the risk of breast cancer in the general population. The safety data regarding ovarian stimulation for oocyte collection is reassuring, with no apparent increased breast cancer risk following these procedures 1.

Evidence Overview

Safety of IVF and Breast Cancer Risk

The available clinical evidence on IVF and breast cancer risk is largely reassuring:

• According to the 2023 ESMO guidelines, the limited safety data available regarding ovarian stimulation for oocyte collection are reassuring, with no apparent increased breast or ovarian cancer risk following these procedures 1.

• Multiple studies have examined this question with most showing no significant association between IVF treatment and increased breast cancer risk 2.

Special Considerations

While the general risk appears minimal, certain subgroups may warrant additional consideration:

1. Age at IVF initiation: Some research suggests women who begin IVF after age 30 may have a slightly increased risk 3.

2. Family history: One study indicated that infertility treatment might be associated with an increased risk of borderline significance among women with a family history of breast cancer 2.

3. Multiple pregnancies after IVF: There is a hypothesis that women who have multiple births after complete embryo implantation may have a higher breast cancer risk (HR 1.86), possibly related to higher VEGF levels 4.

4. Timing: There may be a transient increase in breast cancer detection in the first year after IVF, likely due to earlier diagnosis during the treatment process rather than a true causative relationship 2.

Recommendations for Clinical Practice

For Women Without Genetic Risk Factors:

• IVF can be recommended without specific concerns about breast cancer risk
• Standard breast cancer screening based on age and risk factors should be followed

For Women With Hereditary Cancer Syndromes:

• Sperm cryopreservation and oocyte or embryo cryopreservation are the preferred fertility preservation options for patients with hereditary cancer syndromes 1
• Patients with hereditary cancer syndromes should be informed about prenatal diagnosis and preimplantation genetic testing (PGT) options 1
• For BRCA mutation carriers, the available safety data are reassuring regarding ovarian stimulation for oocyte collection 1

For Breast Cancer Survivors:

• Gonadotropin stimulation as part of IVF in women with previous breast cancer was not associated with an increased risk of breast cancer relapse in a large retrospective study 5
• Post-treatment pregnancies in BRCA-mutated breast cancer survivors should not be discouraged 1

Key Takeaways

1. The majority of evidence indicates no significant association between IVF and breast cancer risk in the general population.

2. Women with hereditary cancer syndromes or previous breast cancer may require individualized counseling but generally can be reassured about IVF safety.

3. Monitoring for breast cancer according to standard guidelines is appropriate for women undergoing IVF, with no need for additional surveillance based solely on IVF treatment.