Impact of trophectoderm biopsy on serum β-hCG dynamics: PGT cycles vs. non-PGT cycles.

PURPOSE

Pre-implantation genetic testing (PGT), which involves trophectoderm (TE) biopsy, is commonly used to detect genetic abnormalities in embryos. However, its impact on serum β-human chorionic gonadotropin (β-hCG) levels in early pregnancy remains a topic of debate. This study evaluated the effects of TE biopsy on β-hCG dynamics. Serum β-hCG levels on days 9 and 11 post-blastocyst transfer were compared between PGT and non-PGT cycles. Additionally, β-hCG thresholds were explored as potential prognostic markers for success in assisted reproductive technology (ART).

METHODS

This retrospective cohort study was conducted at the Memorial Şişli Hospital, İstanbul, Türkiye, between January 2012 and January 2021. The patients undergoing frozen-thawed single blastocyst transfer were divided into PGT (1698 cycles) and non-PGT (1830 cycles) groups. The serum β-hCG levels on days 9 and 11 after embryo transfer (ET) and the rate of β-hCG increase were compared.

RESULTS

In both groups, higher baseline β-hCG levels and rates of increase were correlated with live birth outcomes than with clinical or biochemical pregnancy loss (p < 0.001). PGT cycles showed lower baseline β-hCG levels across all pregnancy outcomes, but no significant difference in β-hCG increase rates (p > 0.05). After adjusting for confounding factors, PGT cycles were not found to be significantly associated with β-hCG levels.

CONCLUSION

Serum β-hCG dynamics strongly predict live birth and clinical pregnancy. PGT did not significantly affect β-hCG levels after adjustment for confounders.