Does flying after embryo transfer impact implantation?

Objective: To explore whether post-embryo transfer (ET) air travel affects in vitro fertilization (IVF) outcomes, addressing the growing concern in medical tourism where patients frequently travel for fertility treatments.

Methods: This retrospective study was conducted at a private fertility clinic in São Paulo, Brazil, and included 2,135 embryo transfers performed between January 2019 and March 2022. Patients were divided into two groups: individuals who presumably traveled by airplane after ET (Group 2) and those who did not (Group 1). Data were analyzed for demographics, embryo transfer characteristics, and IVF outcomes. Relative risk was estimated using Poisson regression models, adjusting for age and treatment reasons. Significance was set at p<0.05.

Results: 17.94% of patients traveled by plane post-ET. No significant differences were found between the groups in terms of pregnancy (Group 1: 61.99%, Group 2: 62.14%, p=0.94), implantation (Group 1: 34.58%, Group 2: 38.65%, p=0.28), or miscarriage rates (Group 1: 28.51%, Group 2: 32.50%, p=0.32). A sub-analysis of single embryo transfers and top embryos also showed no statistical differences.

Conclusions: Post-ET air travel did not negatively impact IVF treatment outcomes. Further prospective studies are recommended to confirm these findings.