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Sources Cited: CDPH (2009) The California Prenatal Screening
Program retrieved from: wwwcd!hcagov"!rogramsaccessed on:
#ovem$er %&' 20%&
!ests !"at Ma #e $ffered:
CVS (Chorionic Villus Sampling):This may be offered at 10-14
weeks of pregnancy: A small number of cells are taken from
the placenta by experienced doctors. The cells are tested forown
syndrome and Trisomy 1!" and other chromosomeabnormalities.
Ultrasound:A detailed picture of the fetus is made using
sound
wa#es. After 1$ weeks of pregnancy" a specialist examines
thefetus #ery closely for birth defects.
Amniocentesis:This may be offered after 1$ weeks ofpregnancy. A
small amount of fluid is taken out of the uterus byexperienced
doctors. Tests are done for specific birth defects.
Quad Marker Screening
At 15 to 20 %eeks of ®nancThe %uad &arker 'creening
tests four different substancesfrom your blood: A() *Alpha-feto
protein+" h, *human
,horionic onadotropin+" u/ *unconugated striol+ andnhibin. These
screenings assess risks for:
own 'yndrome
Trisomy 1! *mental retardation 2 physical birth
defects+ 3eural Tube efects *anencephaly or spina
bifida+ '5' 6'mith-emli-5pit7 'yndrome *physical
birth defects and mental retardation+
'f ou "ae *S +efore QuadMarker Screening
,horionic #illus sampling *,8'+ is a prenatal diagnostic
test for detecting birth defects at an early stage ofpregnancy.
9ou will get a isk Assessment only for3eural tube defects and '5'.
iagnostic tests for own'yndrome and Trisomy 1! are conducted with
,8'.
!ests Resu,ts (Risk Assessment)
A %uad &arker screening result is sent to your doctorabout
;-10 days after blood draw. Your results are specific
to you. They are either Screen Negative or Screen
Positive.
Screen Negative This means that the risk *chance+ of thefetus
ha#ing any of these birth defects is low4 weeks ofpregnancy.
A genetic counselor will re#iew the test results and
familymedical history. The counselor explains the diagnostictests"
which may be offered.
Down Syndrome is caused by an extra chromosome ?>1*Trisomy
>1+. ,hromosomes are packages of genetic material
found in e#ery cell of the body. @irth defects can occur
whenthere are too few or too many chromosomes. own syndrome isa
common cause of mental retardation and other birth defectsand can
affect women of any age. owe#er as women get older"the chances
increase for ha#ing a bay with own syndrome.
Trisomy 18 is caused by an extra chromosome ?1!. &ostfetuses
with Trisomy 1! are lost through miscarriage. @abiesborn with
Trisomy 1! ha#e mental retardation and physicaldefects.
eural Tu!e De"ects (TD) As a fetus is forming" the neural
tube extends from the top of the head to the end of the
spine.This de#elops into the babyBs brain and spinal cord. The
neuraltube is completely formed by $ weeks after conception.
Chen there is an opening in the spine" it is called spina
!i"ida.This defect often causes paralysis of the babyBs legs. t may
also
cause loss of bowel and bladder control.
Anencephalyoccurs when most of the brain does not de#elop.
This defect causes the death of the fetus or newborn.
A!dominal #all De"ects (A#D)are problems in#ol#ing the
babyBs abdomen and intestines. ntestines and other organs
areformed outside the body. 'urgery after birth is usuallyperformed
to correct the defect.
Smith$%emli$&pit' syndrome (S%&S)', This is a #ery
rarebirth defect. @abies with 'mith-emli-5pit7 syndrome *'5'+
cannot make cholesterol normally. @abies born with thiscondition
are mentally retarded and may ha#e many physicaldefects.
Screen Positive results S5' can also indicate increasedchances
for Congential abnormalities and fetal Demise *fetal
death+. This is why this screening is also called
SCDscreening.
http://www.cdph.ca.gov/programshttp://www.cdph.ca.gov/programshttp://www.cdph.ca.gov/programs
