A significant percentage of women suffer from recurring pregnancy loss reducing the chances of conceiving. The obstetric complications in the majority of the women stem from genetic abnormalities like genomic rearrangements, nondisjunction genetic events, chromosomal aberrations or gametic instability during the early embryo development process.
The connection between Genetic Instability and Recurrent Pregnancy Loss
Fetal abnormality is the most common cause of pregnancy loss during the early first trimester. Parental chromosomal abnormalities are a common etiology related to the subsequent loss of pregnancy mostly during the early trimester. With the genetic abnormality in both or either of the parent, it accounts for a higher chance of fetal chromosomal abnormality. It is identified that both structural or numerical chromosome abnormality in parent or fetus can lead to premature pregnancy loss.
Microarray Technique in Detecting Genetic Abnormality
The chromosomal microarray technique is a powerful diagnostic tool for identifying the presence of genetic abnormalities that might result in recurrent pregnancy loss. The use of microarray is not only limited to a genetic screening of the parents but even in the aborted fetus. It is an advanced technique to diagnose RPL chances through pre-implantation screening.
The chromosomal microarray analysis with SNP based arrays is much advance than karyotyping for prenatal genetic screening. With the microarray technique, the screening for detecting aneuploidy, triploid, or chromosomal imbalance becomes convenient. Chromosomal microarray testing is used as a genetic test for the detection presence of an extra chromosome or missing chromosome within the DNA.
CMA or chromosomal microarray helps in detecting the copy number variants by testing different aspects of chromosomal aberrations:
- The microarray technique successfully identifies the presence of microdeletions or microduplications of a chromosomal segment.
- The screening technique help with the identification of chromosomal number abnormalities including trisomy, monosomy etc.
- The microarray technique identifies unbalanced translocation or imbalance in the chromosomal rearrangement.
The technique uses labels or probes which bind to the targeted and specific regions of the chromosome. With the automated analysis, the technique finds out any genetic abnormality that is potentially the cause of the recurrent pregnancy loss. The accuracy of diagnosis is much higher while using the chromosomal microarray technique in comparison to the karyotyping method.
The screening with microarray helps in identifying the chromosomal submicroscopic imbalance including single nucleotide polymorphism and comparative genomic hybridization. In the CGH based arrays, the DNA sample of the patient and control are labelled with fluorescent colours to bind with probes and hence help identify the abnormality. The SNP microanalysis technique uses high-density oligonucleotides as probes for identifying DNA locations and genetic abnormalities.
Identifying Risk of Pregnancy Loss through Screening
Planning to start a family is a big decision but it involves several factors for safe conceiving and giving birth to a healthy child. The microarray is an advanced screening technique that encompasses enable conducting pre-implantation genetic testing to detect genetic abnormalities in couples. The couples who have suffered from recurring pregnancy loss are referred with genetic counselling to identify the future risk or understand the reason behind it.
The microarray analysis is an effective technique that is affordable and prevents from undergoing expensive treatment and evaluation. As microarray detect the abnormality, it strongly analyzes and evaluates the future risk of recurrent pregnancy loss. As it helps in detecting DNA copy numbers, it is superior to the traditional karyotyping method. With such genetic screening, it estimates the potential chances of women to conceive and deliver safety.
