Repeat Trophectoderm Biopsy for PGT: A Case Report of a Healthy Birth After Three Attempts

Sim PK, Nadkarni P. Birth of a Healthy Infant Following Three Times Biopsy of Trophectoderm from the Same Blastocysts for PGD Alpha and Beta Double Thalassaemia — Case Report. Poster presented at the ASPIRE (Asia Pacific Initiative on Reproduction) Conference, 2018. KL Fertility & Gynaecology Centre, Kuala Lumpur, Malaysia.

Funding and disclosures: No declarations available (conference poster). The authors report no competing interests.

Preimplantation genetic testing for monogenic disorders (PGT-M) is widely applied in IVF centres to identify embryos unaffected by serious inherited conditions before transfer. In Asia, alpha and beta thalassaemia are among the most prevalent autosomal recessive monogenic disorders, making them a common indication for PGT-M.

PGT-M requires trophectoderm biopsy at the blastocyst stage (day 5–7), followed by whole genome amplification (WGA) and genetic analysis. Amplification failure — in which an insufficient or poor-quality DNA sample prevents a diagnostic result — occurs in a minority of biopsy cycles and necessitates re-biopsy of the same embryo. This is of particular concern in patients with a limited number of available embryos, where discarding an embryo on the basis of an inconclusive rather than affected result is clinically unacceptable.

The central clinical question motivating this case report is: what is the reported maximum number of trophectoderm re-biopsies of a single blastocyst that has subsequently resulted in a live birth?

A couple from the Maldives, in whom both husband and wife carry the alpha and beta thalassaemia gene, requested PGT-M following IVF at KL Fertility & Gynaecology Centre.

After controlled ovarian stimulation, 11 oocytes were collected, of which 7 were mature (MII). Four oocytes were fertilised. Two blastocysts developed and were biopsied (Biopsy 1). Whole genome amplification failed on both blastocysts. Both blastocysts were warmed and re-biopsied (Biopsy 2). Whole genome amplification failed again. Both blastocysts were re-warmed and biopsied for a third time (Biopsy 3). Diagnosis was successful after this third attempt.

Table 1. Clinical course summary

Genetic diagnosis following the third biopsy identified one blastocyst as a beta thalassaemia carrier and the second as unaffected. The unaffected blastocyst was transferred in a natural cycle.

The transfer resulted in the live birth of a healthy baby boy. The couple declined confirmatory prenatal diagnosis by amniocentesis or chorionic villus sampling (CVS). The child was reported as healthy at 6 months of age at the time of this report.

Amplification failure following trophectoderm biopsy has been reported in approximately 2.5% of biopsied blastocysts in multicentre data, most commonly attributable to technical amplification failure, poor DNA quality related to embryo quality, or suboptimal biopsy timing or technique rather than intrinsic embryo defects.

A prior published case reported successful implantation and live birth following triple biopsy (across oocyte, cleavage, and blastocyst stages) for a beta thalassaemia family, establishing precedent for live birth following extensive biopsy procedures.

A 2024 systematic review and meta-analysis specifically examining the impact of double biopsy and double vitrification on clinical outcomes following euploid blastocyst transfer found significantly lower clinical pregnancy and live birth rates in the double-biopsy group compared with single-biopsy controls, though no significant difference in blastocyst survival after thawing, and no significant difference in neonatal birth weight or gestational age among live births. The authors note that this meta-analysis pertains to PGT-A (chromosome screening) cycles with a single re-biopsy; outcomes following PGT-M cycles and after a third biopsy specifically represent a substantially smaller evidence base, with this case and a small number of others constituting most of the available published data.

This case provides evidence that a healthy live birth is achievable following three trophectoderm biopsy attempts of a single blastocyst, suggesting that multiple re-biopsies need not necessarily be considered contraindicated in patients with no other available embryos. However, the case should be interpreted conservatively: it demonstrates possibility, not typical expectation. The published literature indicates that re-biopsy is associated, on average, with reduced pregnancy and live birth rates, and the available data on three-time biopsy specifically are too limited for reliable rate estimation.