Tonsils and adenoids - Lymphatic tissues that play a role in circulation
and immunity. Tonsils are located in the throat, while adenoids are
located behind the nose. Individuals who develop repeated infections o
the tonsils and adenoids may have them removed to prevent future
infections.
Low tone - Low muscle tone, or hypotonia, indicates that the muscles
have a decreased resistance, making them more stretchy. Hypotonia can
manifest as muscle weakness and increased flexibility. You can learn
more about hypotonia here.
Alpha-Fetoprotein (AFP) Test
What is an alpha-fetoprotein (AFP) test?
Alpha-fetoprotein (AFP) is a protein produced in the liver of a
developing fetus. During a baby's development, some AFP passes
through the placenta and into the mother's blood. An AFP test
measures the level of AFP in pregnant women during the second
trimester of pregnancy. Too much or too little AFP in a mother's blood
may be sign of a birth defect or other condition. These include:
A neural tube defect, a serious condition that causes abnormal
development of a developing baby's brain and/or spine
Key Terms Down syndrome, a genetic disorder that causes intellectual disabilities
AFP - Alpha-fetoprotein (AFP) is produced by the and developmental delays
fetus during development. AFP diffuses across the Twins or multiple births, because more than one baby is producing
placenta into the maternal bloodstream, so AFP AFP
levels are measured by a simple maternal blood Miscalculation of due date, because AFP levels change during
test. AFP levels above or below normal can be pregnancy
indicative of developmental problems. You can Other names: AFP Maternal; Maternal Serum AFP; msAFP screen
learn more about AFP testing here.
What is it used for?
Apgar score - A measure of the health of a An AFP blood test is used to check a developing fetus for risk of birth
newborn based on an assessment of key metrics, defects and genetic disorders, such as neural tube defects or Down
such as breathing, heart rate, and reflexes. syndrome.
Why do I need an AFP test?
ASD - An atrial-septal defect (ASD) is a hole in The American Pregnancy Association says that all pregnant women
the wall between the two atrial chambers of the should be offered an AFP test sometime between the 15th and 20th
heart, leading to less efficient oxygen circulation week of pregnancy. The test may be especially recommended if you:
in the blood. This is a congenital defect, meaning
that it is present at birth. Small defects can close Have a family history of birth defects
up on their own, but larger defects can require Are 35 years or older
surgery to repair. You can learn more about ASD Have diabetes
here.
, What happens during an AFP test? Atrial septal defect (ASD)
A health care professional will take a blood sample from a vein in Atrial septal defect (ASD) is a heart defect that is present at birth
your arm, using a small needle. After the needle is inserted, a (congenital).
small amount of blood will be collected into a test tube or vial.
You may feel a little sting when the needle goes in or out. This As a baby develops in the womb, a wall (septum) forms that divi
usually takes less than five minutes. the upper chamber into a left and right atrium. When this wall do
not form correctly, it can result in a defect that remains after birth
Will I need to do anything to prepare for the test? This is called an atrial septal defect, or ASD.
You don't need any special preparation for an AFP test.
Causes
Are there any risks to the test? Normally, blood cannot flow between the two upper heart
There is very little risk to you or your baby with an AFP blood chambers. However, an ASD allows this to happen.
test. You may have slight pain or bruising at the spot where the
needle was put in, but most symptoms go away quickly. Another When blood flows between the two heart chambers, this is called
test called amniocentesis provides a more accurate diagnosis of shunt. Blood most often flows from the left to the right side. Whe
Down syndrome and other birth defects, but the test has a small this happens the right side of the heart enlarges. Over time pressu
risk of causing a miscarriage. in the lungs may build up. When this happens, the blood flowing
through the defect will then go from right to left. If this occurs,
What do the results mean? there will be less oxygen in the blood that goes to the body.
If your results show higher than normal AFP levels, it may mean
your baby has a neural tube defect such as spina bifida, a Atrial septal defect
condition in which the bones of the spine don't close around the Atrial septal defects are defined as primum or secundum.
spinal cord, or anencephaly, a condition in which the brain does
not develop properly. The primum defects are linked to other heart defects of the
ventricular septum and mitral valve.
If your results show lower than normal AFP levels, it may mean Secundum defects can be a single, small or large hole. They may
your baby has a genetic disorder such as Down syndrome, a also be more than one small hole in the septum or wall between t
condition that causes intellectual and developmental problems. two chambers.
Very small defects (less than 5 millimeters or ¼ inch) are less lik
If your AFP levels are not normal, it doesn't necessarily mean to cause problems. Smaller defects are often discovered much lat
there is a problem with your baby. It may mean you are having in life than larger ones.
more than one baby or that your due date is wrong. You may also
get a false-positive result. That means your results show a Along with the size of the ASD, where the defect is located plays
problem, but your baby is healthy. If your results show a higher or role that affects blood flow and oxygen levels. The presence of
lower than normal level of AFP, you will likely get more tests to other heart defects is also important.
help make a diagnosis.
ASD is not very common.
Learn more about laboratory tests, reference ranges, and
understanding results. Symptoms
A person with no other heart defect, or a small defect (less than 5
Is there anything else I need to know about an AFP test? millimeters) may not have any symptoms, or symptoms may not
AFP tests are often part of a series of prenatal tests called multiple occur until middle age or later.
marker or triple screen tests. In addition to AFP, a triple screen test
includes tests for hCG, a hormone produced by the placenta, and Symptoms that do occur may begin at any time after birth throug
estriol, a form of estrogen made by the fetus. These tests can help childhood. They can include:
diagnose Down syndrome and other genetic disorders.
Difficulty breathing (dyspnea)
If you are at higher risk for having a baby with certain birth Frequent respiratory infections in children
defects, your provider may also recommend a newer test called Feeling the heart beat (palpitations) in adults
cell-free DNA (cfDNA). This is a blood test that can be given as Shortness of breath with activity
early as the 10th week of pregnancy. It can show can show if your
baby has a higher chance of having Down syndrome or certain
other genetic disorders.
