A simplified technique for embryo biopsy for preimplantation genetic diagnosis.

OBJECTIVE

To report a simplified embryo biopsy method for preimplantation genetic diagnosis (PGD).

DESIGN

Technique and method.

SETTING

A regional hospital in vitro fertilization (IVF) laboratory and private reproductive medicine clinic.

PATIENT(S): Women undergoing IVF and PGD.

INTERVENTION(S): Blastomeres were successfully isolated from day-3 embryos at various stages.

MAIN OUTCOME MEASURE(S): Blastomere integrity after biopsy, time of biopsy procedure, and subsequent blastocyst developmental rate.

RESULT(S): Twenty embryos derived from abnormally fertilized oocytes (one pronucleus or three pronuclei) were used for biopsy at four-cell to 10-cell stages (day 3) by a laser zona drilling and assisted hatching micropipette delivery of culture medium inside the zona to push one blastomere out. Biopsies of all embryos using this method were successful. In two cases for PGD, fourteen 6-9-cell and four 3-4-cell stage embryos were successfully biopsied by this method. Ten out of 14 embryos from the 6-9-cell stage developed to hatching or hatched blastocysts. When two hatched blastocysts were vitrified, warmed, and cultured, both reexpanded, showing normal morphologic features.

CONCLUSION(S): This technique is easy to learn, less damaging to the embryos, and less time consuming. It can be used for all stages of embryos without damage to either embryos or isolated blastomeres. It is an alternative method for embryo biopsy in PGD.