Genetic findings in miscarriages : future directions

Purpose Early pregnancy loss leads to a devastating situation for many couples. Genetic disorders found in the pregnancy tissue are a frequent cause of miscarriages. It is unclear whether maternal age or previous miscarriages are associated with a higher chromosomal anomaly rate. This study aimed to determine the cytogenetical distribution of chromosomal disorders in couples after one or more previous miscarriages as well as the influence of maternal age. We found the prevalence of chromosome abnormalities in women facing a single sporadic miscarriage to be ۴۵%. The prevalence of chromosome abnormalities in women experiencing subsequent miscarriage after preceding recurrent miscarriage proved to be comparable: ۳۹%. More chromosome abnormalities are detected by conventional karyotyping compared to FISH or MLPA only (chromosome region specific techniques), and the same number of abnormalities compared to QF-PCR (chromosome region specific techniques) and chromosomal‐CGH and array-CGH (whole genome techniques) only. Molecular techniques could play a role as an additional technique when culture failure or maternal contamination occurs: recent studies show that by using array-CGH, an additional ۵% of submicroscopic chromosome variants can be detected. Because of the small sample size as well as the unknown clinical relevance of these molecular aberrations, more and larger studies should be performed of submicroscopic chromosome abnormalities among sporadic miscarriage samples. For recurrent miscarriage samples molecular technique studies are relatively new. It has often been suggested that miscarriages are due to chromosomal abnormalities in more than ۵۰%, but the present review has determined that chromosomal and submicroscopic genetic abnormalities on average are prevalent in maximally half of the miscarriage samples.

کلیدواژه ها:

Miscarriage ، Recurrent miscarriage ، Number of previous miscarriages ، Molecular genetic abnormalities