Prenatal Testing: How They Are Helping In Identifying Any Genetic Disorders

During pregnancy, it’s natural for mothers to have both excitement and concern about their baby’s health. Understanding potential genetic disorders and having access to information about your baby’s health can provide peace of mind and help in making informed decisions about prenatal care and any necessary medical interventions.

Non-Invasive Prenatal Testing (NIPT) is indeed highly accurate for screening for genetic disorders. It analyses cell-free foetal DNA circulating in the mother’s blood, making it non-invasive compared to procedures like amniocentesis or chorionic villus sampling, which carry a slight risk of complications. These NIPT tests are based on whole genome and targeted methods employing Next Generation Sequencing (NGS). If NIPT results indicate a higher risk of genetic abnormalities, confirmatory diagnostic tests like amniocentesis or chorionic villus sampling can provide more detailed information for informed decision-making regarding the pregnancy.

Amniocentesis involves extracting a small sample of the amniotic fluid surrounding the foetus in the uterus. This fluid contains cells shed by the baby, which can then be analysed for genetic abnormalities and other health indicators. It’s a more invasive procedure compared to NIPT but provides detailed information about the baby’s health status.

Chorionic villus sampling (CVS) involves taking a small sample of tissue from the chorionic villi, which are tiny finger-like projections on the placenta. These cells have the same genetic makeup as the foetus since they are derived from the fertilized egg. CVS is another diagnostic procedure used to assess the genetic health of the foetus, providing similar information as amniocentesis.

Women with advanced maternal age (35 or older), those who have a history of previous chromosome disorders in the family, abnormal foetal ultrasound findings, or abnormal results from prenatal tests like double, triple, and quadruple markers, can increase the risk of having a baby with conditions like Down syndrome or other trisomy disorders. Being informed about these factors can help expectant parents make proactive decisions about their prenatal care and available options for testing and support.

NIPT is typically performed after 10 weeks of gestation when there is enough cell-free fetal DNA in the mother’s blood for accurate testing. Amniocentesis is usually conducted between weeks 15 and 20 of pregnancy, while CVS is typically done earlier, between weeks 10 and 13 of pregnancy.

NIPT is indeed primarily used to screen for chromosomal disorders such as Down syndrome (trisomy 21), trisomy 18, trisomy 13, and abnormalities in the sex chromosomes (X and Y).

These tests provide valuable information about the genetic health of the foetus, allowing parents to make informed decisions about their pregnancy and healthcare.