Screening Tests to suspect Chromosomal Abnormalities in Baby.


The human diploid cell has total 46 chromosomes classified into 22 pairs of autosomes (44 chromosomes) and 1 pair of sex chromosomes (Female XX & Male XY Chromosomes).


They contain several genes, the basic unit of information that is transferred from one generation to another. This information is translated and expressed through the production of specialized proteins that help the cells to grow, differentiate into different organs and function properly.


The abnormalities of number, size or shape of chromosomes or genes may result in multiple structural, developmental, functional, or metabolic abnormalities in the baby. Some of these may be minor and correctable whereas others may be lethal.

The nature follows the rule, Survival of the Fittest. Hence the major abnormalities that is incompatible to life, results in miscarriage especially in first trimester. In fact, Chromosomal abnormalities are thought to be responsible for at least 50 percent of miscarriages that happen in the first trimester.

The incidence of chromosomal abnormalities in live babies is approximately 0.5-1%. Down syndrome (Trisomy21) is the most common chromosomal disorder among live births. The others are Patau’s syndrome (Trisomy13), Edward’s syndrome (Trisomy18) and Turner’s syndrome (Monosomy45X0).

Risk factors for Chromosomal Abnormalities in baby?

  • Advanced maternal age > 35 years.
  • Previous child with chromosomal/ genetic abnormalities.
  • Family history of anomalous baby with genetic/ chromosomal/ structural abnormalities.
  • Medical disorders like Diabetes or Epilepsy in mother.
  • Mothers on essential drugs for Cardiac or Neurological diseases which has teratogenic side effects like Acitrom, Warfarin, Valproate etc.

Diagnostic Tests to Detect Fetal Abnormalities:

Diagnostic tests


The information is shared to create awareness towards Pregnancy and Childcare to reduce maternal and child deaths. At most care has been taken by the author to include the verified information from authentic sources. However, kindly discuss the same with your health care provider before implementation.