If you’ve just found out that you’re expecting and have turned into a bundle of nerves because you’re not sure if baby will be OK, don’t worry. You’re not alone.
Thankfully, prenatal testing has come a long way, and there is an array of tests available which allows mums to be better informed about the health of the precious bub that you are expecting.
Prenatal tests are important as they help identify if the baby has any potential chromosomal irregularities or possible abnormalities from an early stage. It is always good to know that you have options available in order to make the best decisions for yourselves and most specially, your baby.
The following information serves as a guide on the types of screening tests that mums can consider when they are expecting.
Screening tests in pregnancy
Nuchal Translucency (NT) and First Trimester Screen (FTS) are the most common tests taken by mums-to-be. Both tests are performed between Week 11 to 14 of the gestation period using an ultrasound to measure the thickness of the foetal neck. With FTS, however, drawing of blood sample is still required for analysis. Besides, accuracy of both tests are not high, at only up to 84 per cent [1,2].
Another screening test is the Quad Screen (or quadruple screen/AFP4/Multiple Marker/Second Trimester Screen), a blood test done later in pregnancy between week 15 to 18. Most mums who missed the timeframe for FTS would usually go for the Quad Screen. However, it has been found to be less accurate than the first trimester screen test.
The Non-Invasive Prenatal Test (NIPT) though, has the longest window from week 10 to 20. This test only requires a basic blood sample from the mum to examine the cell-free DNA of the baby, thus making it safer than the other options, such as Amniocentesis. NIPTs, such as iGene, are one of the most accurate screening tests with a high detection rate of more than 99.9% for Trisomy 21 (Down Syndrome), Trisomy 18 (Edwards Syndrome) and Trisomy 13 (Patau Syndrome) [3,4]. The turnaround time for the results can be received within 5 to 7 working days. Obviously, this means less waiting time, and panic moments.
NIPTs are gaining popularity as it has proven itself to be increasingly reliable compared to other prenatal blood tests. With its high accuracy rate and faster turnaround time for results, mothers will have greater peace of mind. Having to worry is the last thing mums should do during their pregnancy.
There are a lot of things to consider when you’re expecting. Most screening tests simply produce results that can only be concluded as either abnormal or normal without identifying any specific cause in cases of abnormality in the results. This is another hurdle that one can experience during pregnancy. An ideal next step after screening is for mums to consider taking a diagnostic test to make sure.
Diagnostic tests in pregnancy
The two most common pregnancy diagnostic tests are Chorionic Villus Sampling (CVS) and Amniocentesis. Both are invasive methods of diagnostic tests that are carried out during pregnancy, which identify genetic disorders or chromosomal abnormalities.
CVS is done within week 10 to 13 of gestation. The procedure involves either the insertion of a needle into the uterus or guidance of a thin tube through the cervix to access the placenta and obtain a sample of chorionic villus cells.
Amniocentesis is a method similar to CVS and is carried out later in pregnancy at week 16 to 20. It entails ultrasound-guided withdrawal of amniotic fluid via a long, thin needle that is inserted through one’s abdominal wall and into the sac of fluid around the baby. It serves as an option for those who had to wait for previous screening results, but did not receive them in time to take the CVS test. Both CVS and Amniocentesis procedures can be uncomfortable with a risk of miscarriage and infection.
Above all, timing plays a significant role in your pregnancy journey.
The availability and accessibility of these screening tests give both you and your baby the best start at life possible. For expectant mothers, knowledge about what you are going through reduces anxieties and worries. It definitely provides you with the peace of mind during pregnancy and also keeps you prepared on what to expect.
However, prenatal tests are based on the potential results, which far outnumber the real risks. Awareness and preparedness, are powerful knowledge that will help empower you in improving your pregnancy, and the future life of your baby. It is only prudent for you to monitor the development and progression of the baby’s growth very closely.
The impact of such decisions can determine the rest of your child’s life. If there are any uncertainties about what tests to take, or even whether or not to take it, you should consult your doctor, or a genetics counsellor.
This blog post is sponsored by INEX / iGene Prenatal Test.
For more information, please visit www.igeneprenataltest.com.
1 Lewis, C. et al. Public Health Genomics 2013.
2. Bianchi et al. 2014. The New England Journal of Medicine, 2014 Feb, 370:799-808.
3. Dan et al., Prenatal Diagnosis 2012;32;1-8.
4. Jiang F et al, BMC Medical Genomics, 2012, 5:57