In a study published in the October 2012 issue of Fertility & Sterility, results of preimplantation genetic screening (PGS) with comparative genomic hybridization (CGH) showed a significant decrease in the miscarriage rate in a group of patients with previous idiopathic recurrent pregnancy loss.
They analyzed a total of 2,282 embryos of which 35% were normal (euploid) and 60% were abnormal (aneuploid). There was 181 embryo transfer cycles of which 100 (55%) conceived of which 94 pregnancies were ongoing or delivered. The miscarriage rate was only 6.9%, which is much less than the expected 33.5% in a control population of patients with recurrent pregnancy loss and 23.7% in an infertile population.
These results suggest that idiopathic recurrent pregnancy loss is mostly caused by chromosomal abnormalities in embryos. This finding may mean that with the improvements in PGS utilizing trophectoderm biopsies in blastocysts and CGH to assess all chromosomes that PGS might be a reasonable treatment for recurrent pregnancy loss when other factors have been ruled out.