Double marker test is a blood test conducted during the first trimester of pregnancy to determine the presence of chromosomal defects in the baby. It plays a crucial role in helping to know if there is a possibility for a baby to develop neurological disabilities such as Down’s syndrome, Edward’s syndrome or Patau syndrome.
This test is conducted between your 10 to 14 weeks of gestation. It is intended to identify any abnormalities of chromosomes, because the presence of abnormalities can lead to serious disorders in fetus. These can severely affect the growth of fetus in the mother’s womb and at a later stage as well.
Down’s syndrome is a condition in which chromosomal defects cause intellectual and physical disabilities such as elongated face, short stature and impaired learning. Edward’s syndrome can result in low birth weight, critical organ damage, abnormally small head and severe developmental defects. Patau syndrome is a condition in which babies are born with severe intellectual and physical abnormalities and serious complications which make it impossible for newborns to live beyond their first week. You should know that chromosomal anomalies are very rare occurrence and this test is not required to be taken by every pregnant woman.
How the test is done?
This test is recommended by doctors to women who are aged more than 35 years or if either of the spouse’s family has a history of congenital abnormalities or either of the spouse’s family has a history of diabetes. Double marker test involves blood test and an ultrasound scan. Based on the ultrasound scan for Nuchal fold in fetus, the blood sample results are checked for hormone and protein. The levels of these two in blood is important in determining chromosome defects.
Advantages of Double Marker Test
- This test is considered accurate enough to detect any abnormalities of chromosomes.
- Since the test is conducted in the early stages of pregnancy, it is possible to identify any abnormalities in the initial months itself and to take a decision.
- If any abnormality is detected, there is still sufficient time to get additional tests for confirmation.
- You may decide to terminate the pregnancy in case of an abnormality in the early stage which involves less complications.
- This test helps keep a check on pregnancies in which there maybe a possibility of pre-eclampsia or fetal growth restriction development.
Disadvantages of double marker test
- This test is expensive and so, it is recommended by the doctors only when necessary.
- The test may not be available in every city or clinic because of the equipment required and its cost.
- The test results depend on the equipment quality and the doctor’s abilities to conduct the procedure.
- If the test shows positive, additional tests maybe required to detect and confirm the problem.