Fetal medicine is an upcoming branch of Obstetrics where the fetus is given the primary care right from screening to diagnosis and management of a fetal problem. Read more at http://bangalorefetalmedicine.com/

1. www.bangalorefetalmedicine.com/
Fetal Medicine
Specialist
Bangalore Fetal Medicine Center

2. Fetal medicine is an upcoming branch of Obstetrics where
the fetus is given the primary care right from screening to
diagnosis and management of a fetal problem
Screening For Down Syndrome
Dear Parents to be, Congratulations!
You are stepping into the one of the most rewarding journey of
your life, the destination of which will be blissful parenthood. It is
indeed our pleasure to support you through this journey as the
Fetal Medicine Unit. The endeavour of Fetal Medicine is to
safeguard the health and well being of your unborn baby. We
specifically follow the growth and development of the fetus and
look for any problems and suggest the corrective treatment.
Another important aspect in fetal well being is to look for
chromosomal or genetic problems that may be inherent and that
can profoundly affect the quality of life after birth. In this context,
we want to educate you about screening for Down Syndrome.

3. What is Down Syndrome?
Down Syndrome (DS) is a chromosomal disorder in which the
affected individual has one extra chromosome in addition to what is
the normally allocated number of chromosomes. Every human being
has 46 chromosomes arranged in 23 pairs. In people with Down
Syndrome, the chromosome pair number 21 has three copies
instead of two so that the total number of chromosomes is 47
instead of the normal 46. Each man’s sperm has 23 chromosomes
and so does each woman’s egg, so that when conception occurs
and the sperm fertilises the egg, a new human being with a full
complement of chromosomes is formed. Sometimes mistakes occur
and lead to what are described as chromosomal abnormalities.
Down Syndrome is one of the commonest of these. At conception,
instead of one number 21 chromosome from the father and one from
the mother coming together, a third chromosome creeps in and is
then duplicated in every cell of the baby’s body. Down Syndrome,
also called Trisomy 21, is the most common chromosomal
abnormality, occurring approximately once in every 600 births.

4. Why should we test for Down’s syndrome?
Down Syndrome is the most common chromosomal abnormality and
can have a major social, financial and emotional impact on a family.
It is the commonest cause of global developmental delay in children,
which is NOT inherited.
What are the characteristics of Down’s syndrome?
People with Down Syndrome will all have some degree of learning
difficulty. Many people with Down’s will go to ordinary schools and
lead semi-independent lives, but others will need full-time care.
Certain medical conditions are more likely to occur in people with
Down Syndrome.
These include:
♥ heart defects, which occur in one in three children with Down’s
♥ digestive tract defects
♥ problems with sight
♥ problems with hearing

5. All people with Down’s will have certain physical characteristics,
such as eyes that slant upwards and outwards, a single crease
running across the palm of the hand, low-set ears and small hands.
Babies born today with Down Syndrome can expect to live between
40 and 60 years on average.
Are you at risk of having a baby with Down’s syndrome?
Every mother is at a risk of having a child with Down Syndrome and
this increases with the mother’s age, especially over the age of 35.
However, majority of babies with Down’s syndrome are born to the
relatively younger mothers because there are more number of
pregnancies in women below the age of 35.
What can you do to find out whether or not you baby has
Down’s syndrome?
The mother can undergo certain tests in pregnancy. There are two
types of test available – screening tests and diagnostic tests. A
screening test estimates the risk of your baby having Down
Syndrome. It only tells you whether or not you are at particularly high
risk of having a baby with Down Syndrome. This does not confirm
the chromosome status of your baby. A diagnostic test can give you
a definite diagnosis, but also carries a small risk of miscarriage.

6. What screening tests are available?
There are many different screening tests available. There are
ultrasound tests, blood tests and a combination of the two.
The ultrasound tests include the nuchal transluscency scan between
11- 14 weeks of pregnancy and the anomaly scan between 18-20
weeks. In these scans, apart from the general growth and
development, we look for markers for Down Syndrome in the fetus
and depending on the presence or absence of these markers, we
assess the risk for Down Syndrome The blood tests include the first
trimester test which measures two hormones in the mother – beta
HCG and PAPP-A between 10-14 weeks of pregnancy or the second
trimester triple serum screening in which three hormones (beta
HCG, AFP and uE3) are measured in the maternal blood between
15 – 20 weeks. If both ultrasound and blood tests are done, then the
risk assessment obtained from both can be combined to get a more
accurate final risk assessment. These are the screening tests. They
can’t tell you for certain that your baby has or has not got Down
syndrome. A screening test can help you decide whether or not to
have a diagnostic test.

7. The diagnostic test is either a CVS (Chorionic Villus Sampling)
or Amniocentesis which will confirm the chromosomal status of
the fetus and tell you definitely whether or not your baby has
Down Syndrome. However, these are invasive tests and they
carry a risk of miscarriage. Hence they are generally offered
only if the screening tests are suggestive of a problem. A cut-off
point of 1 in 300 is usually used at BFMC. If your risk is less
than that, you will be described as “screen negative” which
means that you are unlikely to be carrying a baby with Down’s
(but it’s not impossible). We will discuss all results with the
parents. However, if any couple consider their ‘personalized risk
assessment’ high enough to warrant an invasive test, this will be
discussed and their opinion respected. These tests will detect
many pregnancies affected by Down syndrome, but they will
also identify some pregnancies as being ‘at risk’ of Down
Syndrome when, in fact, they are not; these are known as
“false-positives”.

8. Eligibility and detection rates:
Test
Test type
Detection rate
First Trimester
Double Marker Blood
Test
Blood test
67%
Combined / OSCAR
Test (Blood test at
10-13 weeks
followed by NT scan
at 12-13 weeks)
Blood + Scan
95%
NT Scan – 11-13+6
weeks
Scan
80%
Second Trimester
Triple Blood Test
15-20+6 weeks
Blood test
65%
Genetic Sonogram –
18-23 weeks
Scan
60-70%
SEQUENTIAL
SCREENING
COMBINES ALL
THE ABOVE
Blood + Scan
97-98%

9. WE HAVE ADDITIONAL INFORMATION LEAFLETS DETAILING
FIRST AND SECOND TRIMESTER SCREENING TESTS.
The Nuchal Translucency (NT) Scan
First Trimester Combined / “Oscar” Test
Second Trimester Triple / Quadruple Test
Contact:
BFMC, Address: 2E, 2nd Floor, RICH HOMES, 5/1, Richmond
Road
Bangalore 560 025, India
http://bangalorefetalmedicine.com/

10. WE HAVE ADDITIONAL INFORMATION LEAFLETS DETAILING
FIRST AND SECOND TRIMESTER SCREENING TESTS.
The Nuchal Translucency (NT) Scan
First Trimester Combined / “Oscar” Test
Second Trimester Triple / Quadruple Test
Contact:
BFMC, Address: 2E, 2nd Floor, RICH HOMES, 5/1, Richmond
Road
Bangalore 560 025, India
http://bangalorefetalmedicine.com/