Chromosomal Analysis of Product of Conception
Fetal loss is the most common pregnancy complication, occurring in 25-30% of recognized pregnancies. In fetal loss prior to 20 weeks of gestation, the fetal and placental tissues are referred to as products of conception (POC). Fetal loss after 20 weeks of gestation is referred to as an Intrauterine Fetal Demise (IUFD). The most common cause of early pregnancy loss is chromosomal abnormalities in the fetus, which account for at least 50-60% of all first trimester losses. Chromosomal abnormalities in IUFDs occur less frequently, at a rate of about 20%. Chromosomal analysis on POC or IUFDs through genetic testing may help identify the cause of pregnancy loss and improve management of future pregnancies by considering Assisted Reproductive Techniques and Comprehensive Chromosomal Screening to avoid the recurrence of miscarriages.
Who should consider chromosomal analysis of POC or IUFD?
- Those who have had 2 or more miscarriages (from normal or ART conception)
- Confirmation of abnormal prenatal results
- When malformations are evident in the aborted fetus
- Couples interested in determining the risk of miscarriage recurrence
Test Methods and Results:
For the past three decades, chromosomal analysis on POCs and IUFDs has been performed by karyotyping. Unfortunately, in 22-55% of cases, it is not possible to find a result after karyotyping products of conception.
An alternative and improvement to the karyotyping method is Microarray Analysis. Microarray Analysis does not rely upon cell culture and is able to provide results in approximately 95% of cases. Microarray Analysis may be performed directly on fresh POC tissue as well as on samples from which a karyotype cannot be performed, such as formalin-fixed, paraffin-embedded (FFPE) POC tissue.
The Microarray Analysis used at Fakih IVF Fertility Center combines the use of Single Nucleotide Polymorphism (SNP) and oligomers and allows us to identify polyploidy – a common cause of spontaneous pregnancy loss caused mainly by molar pregnancy – and maternal cell contamination. The Microarray Analysis turnaround time is approximately 7 working days.