J. Cieslak et al., Three-dimensional partial zona dissection for preimplantation genetic diagnosis and assisted hatching, FERT STERIL, 71(2), 1999, pp. 308-313
Objective: To develop a new approach to partial zona dissection of oocytes
and embryos for facilitating preimplantation genetic sampling and assisted
hatching.
Design: Controlled clinical study.
Setting: Preimplantation genetic diagnosis and IVF program, Reproductive Ge
netics Institute/IVF Illinois, Chicago, Illinois.
Patient(s): Three hundred forty patients undergoing IVF in whom preimplanta
tion genetic diagnosis or assisted hatching was required.
Intervention(s): Three-dimensional partial zona dissection and conventional
partial zona dissection were performed. with the use of a simple microneed
le, on embryos before preimplantation genetic sampling or on day 3 of embry
o development before ET.
Main Outcome Measure(s): pregnancy rate, implantation rate. and ease of pre
implantation genetic sampling.
Result(s): A pregnancy rate of 42% and an embryo implantation rate of 17.6%
were obtained in the group in which three-dimensional partial zona dissect
ion was performed, compared with a pregnancy rate of 33% and an implantatio
n rate of 14.7% in the control group, which underwent conventional partial
zona dissection. Preimplantation genetic sampling can be performed without
distortion of the blastomere configuration in the embryo.
Conclusion(s): Three-dimensional partial zona dissection is a safe: and sim
ple mechanical means of creating an opening sufficient for the atraumatic r
emoval of material from oocytes and embryos for preimplantation genetic dia
gnosis and assisted hatching. (Fertil Steril(R) 1999;71:308-13. (C) 1999 by
American Society for Reproductive Medicine.)