What is an Alpha-fetoprotein (AFP) Test?

Alpha-fetoprotein screening is a blood test for pregnant women. It can be used to look for a problem in the baby’s spine or certain other conditions, such as some chromosome problems.

The test measures the level of a protein called alpha-fetoprotein (AFP) in your blood. It is a way to check for some types of birth defects.

AFP is produced by your unborn baby’s liver. Some AFP passes from the baby into your bloodstream. If a baby has certain problems, the level of AFP may be abnormally high or low. Sometimes, however, the AFP level is abnormal when the baby has no problems.
Because the test is not completely accurate, your health care provider will usually order other tests if the AFP levels are high or low.

What problems does the test find?

A high level of AFP may indicate a problem with the spinal cord, brain, or digestive system. Examples of problems that can cause a high AFP are: Spina bifida, kidney problems, severe skin problems, severe chromosome problems (other than Down syndrome), anencephaly, a failure of your baby’s abdomen to close, so that the intestines are enclosed in a sac outside the abdomen a defect in the esophagus (food pipe).

A low level of the protein may indicate Down syndrome. Other possible causes for abnormal levels are: An incorrect due date, the presence of more than 1 baby, miscarriage, a pulling away of the placenta from the uterus, a baby who is smaller than normal, an overweight mother, especially if the mother is African American, or a diabetic mother.

How is the test done?

A small amount of blood is taken from your arm with a needle. The test is done between the 15th and 20th weeks of pregnancy. The blood is collected in tubes and sent to a lab.

It is important to have the test at the right time in your pregnancy. If the AFP level is higher or lower than normal, enough time must remain in your pregnancy for further steps. These steps might include more tests and counseling. Also, for the test to be interpreted properly, you and your health care provider need to be sure of your due date.

Alpha-fetoprotein levels are highest between the 15th and 18th weeks of pregnancy. After this time they slowly decrease.

How will I get the test results?

Your online patient portal or a phone call from the office.

How accurate is the test?

The test is not completely accurate. A baby may have a defect even though AFP levels are normal. Or a baby may be quite normal even though AFP levels are abnormal. Usually, if the first blood test shows normal levels, no further tests are done. If the first test shows abnormal levels of AFP, it may be repeated before other tests are done.

For every 1000 pregnant women tested, about 50 have abnormal test results. Of these 50, just 1 or 2 with high AFP levels have babies with problems. The test finds 90% of babies with anencephaly and 75% with spina bifida.

What if the results are not normal?

Abnormal results indicate the need for further tests, such as: ultrasound scans (a scan of your uterus and the baby with sound waves) amniocentesis (a test of the fluid around the baby) to look at the baby’s chromosomes, cordocentesis, or percutaneous umbilical blood sampling, which is a way to get cells from the baby’s blood that can be tested for chromosome problems.

In some cases, these tests find no reason for abnormal AFP results. Talk to your health care provider about your results and ask questions. Ask if and when you need more tests. If the results of the AFP test and follow-up tests show that your baby does have a serious problem, your provider will talk to you about your choices of treatment.

What are the risks of AFP testing?

There is virtually no risk to you or your baby from this test.

What are the benefits?

Most often, the test reassures you that your baby probably does not have a serious defect. Abnormal results can help you and your health care provider manage your pregnancy better.

Some problems can be treated with surgery while the baby is still in the uterus. If a brain or spinal defect is diagnosed, you and your health care provider can discuss your options. Your provider may plan your delivery in a center equipped to deal with these defects, which may improve the outlook for your baby.

Your provider can offer you counseling to help you prepare for the baby’s problems.

There are also many support groups for families who have children with birth defects. You may find it helpful to get in touch with these groups before or after your baby is born.

What is the Quad Screen?
This is an optional blood test that can determine if your baby is at higher risk for neural tube defects (spina bifida or anencephaly) and chromosomal disorders (such as Down Syndrome) that can cause mental retardation and other birth defects.

When is the test done?
The “Quad Screen” can be done between 15-20 weeks.

It is important to note that these are only screening tests, and do not give definitive answers. It is best to discuss your individual risks with your healthcare provider who will answer any questions.

Non-Invasive Prenatal Testing: Cell Free DNA

Chromosomal abnormalities occur in 1 in 150 live births. This risk increases as a woman ages but can affect patients at any age and is not related to race or ethnicity. Down Syndrome (Trisomy 21) is the most common of these chromosomal abnormalities.

What is cell-free DNA screening?
Cell-free DNA screening is a test that can determine if a woman has a higher chance of having a baby with Down syndrome (Trisomy 21), Trisomy 18, Trisomy 13 or an abnormality in the sex chromosomes (X and Y chromosomes).
With this test, a sample of the woman’s blood is taken after 10 weeks of pregnancy. The test measures the small fragments of fetal DNA in the mother’s blood and can determine the chance of a chromosome problem based on the relative amount of DNA from chromosomes 21, 18, 13 and the sex chromosomes. The results are usually available within two weeks of the blood draw.

Does the test detect all pregnancies with Down syndrome and trisomy 18 and 13?
No. Cell-free DNA screening can detect more than 99 % of Down syndrome pregnancies. It can detect 98% of Trisomy 18 pregnancies, and 99% of Trisomy 13 pregnancies. It is a good test, but it is not perfect.

What if cell-free DNA screening indicates a high risk?
There is a chance this test can have a false positive result. Women who are found to be at increased risk can have definitive testing with chorionic villus sampling (CVS) or amniocentesis to find out for sure. Whether or not to have diagnostic testing is a personal choice for each woman and the decision is discussed with a high-risk Obstetric doctor and a genetic counselor.

Who should consider cell-free DNA screening?
At Ogeechee OBGYN, this test is offered to any patient who would like it.

It is particularly useful however for women who have a higher-than-average chance of having a baby with a chromosome abnormality. This includes women who will be at least 35 years old at the time of their due date, those with certain abnormalities found during the 20 week ultrasound, and those who have had a previous pregnancy or baby with Down syndrome or trisomy 13 or 18.

Cell-free DNA screening is not as accurate in women with twins and cannot be used in women with triplets.

Is cell-free DNA screening covered by insurance?
Insurance coverage for this test varies based on individual plans, and not all insurance companies cover the testing for all patients.

You should check with your insurer if you are interested in having this test.

Why do I need to get tested  for this?

Most of the population is Rh positive, but around 10-15% of people are Rh negative. During pregnancy and delivery, there can be an exchange of blood between mom and baby.  If an Rh negative mother is carrying an Rh positive baby, their immune system can attack the baby’s blood and result in a life threatening situation for the baby.  

What happens if I am Rh negative?

Rh negative mothers are given an injection of Rhogam (Rh immunoglobulin) to protect against the formation of Rh positive antibodies.

What is the Glucose Challenge Test?

The glucose challenge test, also called the one-hour glucose tolerance test or GCT, measures your body’s response to sugar (glucose).

Why do I need to do The glucose challenge test?
The GCT is done during pregnancy to screen for gestational diabetes. Gestational diabetes is the kind of diabetes that only develops during pregnancy.

How is the GCT done?
The test is done in two steps. First you drink a sugary solution. One hour later, your blood sugar level is measured with a blood draw.

Do I have to stay in the office while I am waiting?
Yes, You’ll need to remain in the office while you wait for your blood sugar level to be tested.

What do my results mean?
The results indicate whether you might have gestational diabetes. Our office will notify you of results and next steps.
If the test results are outside the standard range, you may need further testing to determine the diagnosis. 

Can I eat before my GCT?
Yes, you can eat before your test. We recommend a high protein breakfast and to limit carbs and sugar the day of the test.

What Is Group B Strep?

Group B Streptococcus (GBS) is a type of bacteria often found in the urinary tract, digestive system, and reproductive tracts. The bacteria comes and goes from our body, so most people who have it do not know that they do. GBS usually does not cause health problems.

What Problems Can Group B Strep Cause in Pregnancy?

About 1 out of every 4 women have GBS. In pregnant women, GBS can cause infection of the urinary tract, placenta, womb, and amniotic fluid. Even if they have not had any symptoms of infection, pregnant women can pass the infection to their babies during labor and delivery.

How Does Group B Strep Affect Babies?

When women with BS are treated with antibiotics during labor, most of their babies do not have any problems. But some babies can become extremely sick from GBS. Premature babies are more likely to be infected with GBS than full-term babies because their bodies and immune systems are less developed.

How Is Group B Strep Diagnosed?

Pregnant women are routinely tested for GBS late in the pregnancy, usually between weeks 35 and 37. The test is called a culture, and it involves using a cotton swab to collect samples from the vagina and rectum. These samples are tested in a lab to check for GBS. The results are typically available in 1 to 3 days.

If a test finds GBS, the woman is said to be “GBS-positive.” This means only that she has the bacteria in her body – not that she or her baby will become sick from it.

How Is Group B Strep Treated?

If a woman is tested and found to be GBS positive, she will get intravenous (IV) antibiotics during labor to kill the bacteria. It is best for a woman to get antibiotics for at least 4 hours before delivery. This simple step helps to prevent the spread of GBS to the baby.