Outcome of preimplantation genetic diagnosis of translocations.
OBJECTIVE
To review 35 cases of preimplantation genetic diagnosis (PGD) of translocations with several methods, including telomeric probes.


METHODS
Retrospective study.


METHODS
Clinical IVF laboratory.


METHODS
Thirty-five couples with one partner carrying a chromosomal translocation.


METHODS
PGD of translocation after polar-body or embryo biopsy.


METHODS
Pregnancy outcome.


RESULTS
Several trends were observed. First, PGD can achieve a statistically significant reduction in spontaneous abortion, from 95% to 13%. Second, the chances of achieving pregnancy are correlated with 50% or more of the embryos being chromosomally normal. Third, patients with robertsonian translocations produced fewer abnormal gametes and more pregnancies than did patients with reciprocal translocations. Fourth, a new fluorescence in situ hybridization protocol for PGD of translocations, which involves applying telomeric probes, has proved adequately reliable with a 6% average error rate.


CONCLUSIONS
PGD of translocations achieves a statistically significant reduction in spontaneous abortion, both for polar-body and blastomere biopsy cases. Pregnancy outcome depended on the number of normal embryos available for transfer, with patients having <50% abnormal embryos achieving the most pregnancies. Because robertsonian translocations caused fewer abnormal embryos than reciprocal translocations, they also resulted in higher rates of implantation.
Munné
S
S
The Institute for Reproductive Medicine and Science, Saint Barnabas Medical Center, Livingston, New Jersey, USA. santi.munne@embryos.net
Sandalinas
M
M
Escudero
T
T
Fung
J
J
Gianaroli
L
L
Cohen
J
J
D000022:Abortion, Spontaneous / Q000517:prevention & control; D000328:Adult; D002869:Chromosome Aberrations / Q000235:genetics; D025063:Chromosome Disorders; D010064:Embryo Implantation; D005260:Female; D006801:Humans; D008297:Male; D011247:Pregnancy; D011256:Pregnancy Outcome; D019836:Preimplantation Diagnosis; D012189:Retrospective Studies; D016615:Telomere / Q000235:genetics; D014178:Translocation, Genetic