Preimplantation genetic diagnosis reduces pregnancy loss in women aged 35 years and older with a history of recurrent miscarriages.

Objective: To determine whether preimplantation genetic diagnosis (PGD) and transfer of euploid embryos would decrease spontaneous abortion rates in recurrent miscarriage (RM) patients.
Design: Controlled clinical study.
Setting: In vitro fertilization centers and PGD reference laboratory.
Patient(s): Recurrent-miscarriage patients with three or more prior lost pregnancies with no known etiology.
Intervention(s): Biopsy of a single blastomere from each day 3 embryo, followed by fluorescence in situ hybridization analysis.
Main Outcome Measure(s): The rate of spontaneous abortions in RM subjects undergoing PGD were compared with [1] their own a priori expectations and [2] a comparison group of women undergoing PGD for advanced maternal age (> or =35 years).
Result(s): Before PGD, RM patients had lost 87% (262/301) of their pregnancies, with an expected loss rate of 36.5%. After, they only lost 16.7% pregnancies. This difference was mostly due to reduction in pregnancy loss in the > or =35-years age subgroup, to 12% from an expected 44.5%.
Conclusion(s): Preimplantation genetic diagnosis aneuploidy screening has a beneficial effect on pregnancy outcome in RM couples, especially those in which the woman is aged > or =35 years. Our data indicate that PGD reduces the risk of miscarriage in RM patients to baseline levels.