At Apollo Cradle, experts in maternal-fetal medicine, neonatology and paediatric surgery offer prenatal evaluation, fetal diagnosis and treatment services that consider both you and your baby throughout your pregnancy and after delivery.
Prenatal screening is testing for diseases or conditions in a fetus before it is born. Screening tests tell you your chance of having a baby with Down syndrome, trisomy 18 or structural abnormality such as an open neural tube defect.
Blood tests and an ultrasound, are done starting at 11 weeks of pregnancy.
Screening tests cannot tell you for sure whether or not your baby has one of these three conditions, only the chance of this.
To find out for sure, you would have to decide whether to have a diagnostic test.
A screening test is offered to all women during early pregnancy to assess the risk of the baby being born with Down syndrome, in this pregnancy. If your screening test shows a high risk that the baby has Down syndrome, you will usually be offered a diagnostic test.
Combined First Trimester screening or NT scan: also known as the combined screening or NT scan.
The vast majority of babies are normal. However all women, whatever their age, have a small risk of delivering a baby with a physical or a mental abnormality. In some cases this may be due to chromosomal problems such as Down syndrome, Trisomy 13 or Trisomy 18. These conditions are mainly looked for in the first trimester screening.
Anyone can have a baby with these chromosome abnormalities, however, the chance increases with the mother’s age, but a child with Down Syndrome can be born to a mother of any age.
First trimester screening is not a diagnostic test. This means that it cannot tell you whether your baby has Down syndrome, trisomy 13, or trisomy 18. Instead, the screening provides a probability that your baby might have Down syndrome, trisomy 13, or trisomy 18.
This probability or chance is based on the following criteria: your age, Nuchal Translucency (amount of fluid behind the neck of the fetus on ultrasound), presence or absence of any physical abnormalities on ultrasound, level of three proteins (Fß-hCG, PAPP-A and PLGF) in your blood.
This screening involves an ultrasound assessment of the fetus including the nuchal translucency and the new markers such as nasal bone, tricuspid regurgitation and ductus venosus PI.
The maternal blood is also checked for PAPPA, free beta- HCG and PLGF and an integrated risk assessment is given..
It involves two tests, a blood test and an ultrasound.
Blood Test – It is recommended to have the blood test at week 10 of pregnancy. However, the blood test can be performed up until 13 weeks and 6 days of pregnancy. It analyzes three chemicals called free beta-human chorionic gonadotropin (hCG), pregnancy associated plasma protein-A (PAPP-A), and placental growth factor (PLGF) which are found in the blood of all pregnant women.
Ultrasound – It is recommended to have the ultrasound at week 12 of pregnancy. However, the ultrasound can be performed from 11 weeks through to 13 weeks and 6 days of pregnancy. It is a highly specialized ultrasound.
The sonogram will confirm how advanced your pregnancy is. In addition, a measurement of the fluid underneath the skin along the back of the baby’s neck, called the nuchal translucency (NT), will be taken. The sonogram will also determine if your baby’s nasal bone is present or absent. It will also check the blood flow across the valve of the right heart chamber and look for regurgitation (tricuspid regurgitation) and blood across the ductus venosus, the physiological valve regulating blood to the heart.
Combining your age-related risk with the NT measurement, nasal bone data and blood tests, provides you with one risk figure for Down syndrome and one risk figure for trisomy 13 or trisomy 18.
Because this is a screening test, a positive result (showing an increased risk) does not mean that your baby has a problem, only that further diagnostic tests are options for you to consider. Also, a negative or normal result (one that shows a decreased risk) does not mean that the baby will not have a chromosome abnormality.
It is important to remember that most women will have normal babies, even if they are grouped as high risk.
When the result is “screen positive”, the following options are available: Diagnostic testing by chorionic villus sampling (CVS) performed between 10-13 weeks, diagnostic testing by amniocentesis performed after 15 weeks, second trimester maternal serum screening drawn after 15 weeks to obtain a combined first and second trimester screening result and detailed anatomy ultrasound performed at approximately 18-20 weeks.
Diagnostic tests will usually involve amniocentesis or chorionic villus sampling, which take a small amount of fluid or tissue from around the baby for chromosomal analysis. Both tests have a small risk of miscarriage. CVS and amniocentesis are diagnostic tests that can tell you with greater than 99% accuracy whether or not a baby has a chromosome abnormality.
Final results from the chromosomal analysis may take 2-3 weeks. Usually an interim result may be available in a few days.
Some individuals or couples may elect not to pursue testing or additional testing for various reasons if they are comfortable with the results no matter what the outcome or they choose not to allow any testing that poses any risk of harming the developing baby.It is important to discuss the risks and benefits of testing thoroughly.
The Quad screen also known as the Quadruple marker test or simply the Quad test is a prenatal test that measures levels of four hormones in a pregnant woman’s blood:
Typically, the quad screen is done between weeks 15 and 20 of pregnancy - the second trimester.
The quad screen is done to evaluate your risk of carrying a baby who has any of the following conditions: Down syndrome (trisomy 21), Edwards syndrome (trisomy 18), Spina bifida, and Anencephaly.
The quad screen is optional. Test results only indicate whether you have an increased risk of carrying a baby who has Down syndrome, not whether your baby actually has the condition. If your risk level is moderate or high, you might choose to follow the quad screen with another test that’s more definitive.It is important to consider whether any anxiety caused may be worth it. Would you take the risk of choosing a more invasive follow-up test if screening tests come positive. How would you handle the results and would you handle the pregnancy differently based on a positive result.
Pre-eclampsia is pregnancy induced high blood pressure and is one of the most common life threatening conditions occurring in pregnancy. It occurs in 1 in 50 pregnancies.
Unfortunately, high blood pressure can be dangerous to the mother and baby. The only current treatment is delivery and the timing of this is crucial and needs to balance the maturity of the baby against the condition of the mother.
The likelihood of developing pre-eclampsia is increased by a number of factors including first pregnancy, high body mass index (BMI), and having any previous personal and family history of pre-eclampsia.
In addition to your 11—13 week scan you can opt to have a screening test for this potentially serious condition. There is extensive evidence that early pre-eclampsia is associated with an increased risk to you and your baby’s health.
If detected high risk, better maternal and fetal monitoring would lead to earlier detection of the clinical signs of the disease. Where necessary, medication can be given.
The Pre-eclampsia screening process involves an ultrasound scan to measure the placental blood flow at 11-13 weeks gestation in combination with maternal history, mean arterial blood pressure, serum PAPP-A maternal blood marker and placental growth factor (PLGF).
A routine mid trimester scan should be performed as close to 20 weeks as possible to check not only the baby’s structural development but also growth.At 23 – 24 week it is important to check baby’s growth, uterine artery dopplers, your blood pressure and urine. At this stage if everything is alright your doctor will continue to check your blood pressure and urine throughout the pregnancy on a regular basis till you go into labour.