Screening tests during pregnancy

Chorionic villus sampling (CVS)

Chorionic villus sampling (CVS) is typically offered to you if your screening test for Down’s syndrome reports that you are in the high risk group. CVS accurately detects chromosomal abnormalities in your fetus, and is particularly useful if there is a positive family history of genetic disorders.

Fetal anomaly screening scan

You can expect to have an ultrasound done around the mid part of your pregnancy (between 18 and 22 weeks). The main objective of this scan is to detect any abnormalities in the fetus (also known as fetal anomalies). A special gel will be rubbed across the mother’s tummy as this will enhance the image from the sound waves produced by the sonogram. The doctor will then use the ultrasound wand (called a transducer) and move it across the tummy.

Through this procedure, images of the baby can be seen, measured and recorded. You will be able to look out for the size of the baby and determine the age. Pictures from the scan can also be kept and recorded on a DVD as a memento.

Oral glucose tolerance test (OGTT)

The oral glucose tolerance test (OGTT) is performed to test for Type 2 diabetes and gestational diabetes in pregnant women. With an OGTT, you are required to fast overnight (at least 8 hours). Glucose is given orally and blood samples are taken 2 hours later to determine how quickly the body is able to break down the glucose, or sugar in the bloodstream.

Generally diagnosed during childhood, those who suffer from Type 1 diabetes have problems breaking down glucose as they do not have enough supply of insulin in their body.

On the other hand, Type 2 diabetes usually develops during adulthood. For Type 2 diabetes, the body either doesn’t produce enough insulin or is resistant to insulin.

Gestational diabetes happens when the mother does not have diabetes but has high blood sugar levels as a result of pregnancy. This usually happens during the second trimester.

Click on page 3 for screening tests during the third trimester of your pregnancy…