Testing

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Genetic Testing

At VOB our goal is to take the best possible care of you and your baby (babies). Every pregnancy is unique, and the potential exists for specific problems to be present, even when the pregnancy is progressing normally. These problems are relatively rare, but may represent serious health conditions for your child.

There are a number of screening tests which may be done at various stages during your pregnancy which can help detect the possibility of a health problem for your baby. These basic tests are done by drawing the mother’s blood and sending it to a lab or by doing an ultrasound. They are not perfectly conclusive in diagnosing specific problems; there can be false positive results (indicating something is present when, in reality, it is not) or there can be false negative results (indicating something is not there when, in reality, it is present).

We will do our best to inform you of the usefulness and limitations of each test as it pertains to you and your baby. Since some (or all) of these test may not be covered by your insurance plan, and they are expensive, we will order only those test that you desire and request. Deciding not to have a particular test done is a perfectly reasonable option and will not prevent us from providing you with excellent care throughout your pregnancy.

These tests are accomplished by having an amniocentesis done. This is an invasive test in which a small amount of amniotic fluid which surrounds the fetus is removed from the uterus through a thin needle. An ultrasound of the fetus is performed while the needle is in the uterus to help guide the positioning of the needle. This procedure carries with it increased risk for damage to the fetus and/or a complete miscarriage. It should only be conducted after a thorough dialogue with both our physician and the specialist who will be performing the procedure.

Among the conditions that can be tested (by amniocentesis) for are:

Open Neural Tube Defects

Defects in the spinal column and brain occur in less than 1 in 1000 pregnancies. Adequate folic acid intake around the time of conception and very early pregnancy reduces the risk. These defects can be diagnosed during pregnancy either by ultrasound or a blood test performed during the 2nd semester. Chromosomal Abnormalities

The most common chromosome problems include Down’s Syndrome and Trisomy 18. These problems tend to increase in frequency as a mother’s age increases. The most accurate way to detect these problems involves an amniocentesis, which is an invasive test with some risks. There are blood tests that can be performed in the first or second trimester that can help identify which women are at greater risk.

Cystic Fibrosis (CF)

CF is a genetic problem that affects the secretions of the lungs as well as the pancreas. Children with CF may have normal intelligence and ability, but may need additional medical care. All newborns in Michigan are screened for this disease within 24 hours of birth. It affects only about 1 in 2500 infants born, but up to 1 in 25 people of European descent may carry a gene. There is not a known cure, but early diagnosis helps provide good care in a timely fashion.

Sickle Cell Anemia

This can be diagnosed either with the amniocentesis test, or more frequently with a simple blood test called the hemoglobin electrophoresis test. You and the baby’s father each contribute genes that combine to form the baby’s genetic makeup. If one of the parents’ genes given to the baby has this abnormal hemoglobin deficiency then the baby will have sickle cell trait. If both of the parents’ genes given to the baby have this abnormal hemoglobin deficiency then the baby will have sickle cell anemia. Only individuals with sickle cell anemia will experience the effects of the disorder. This disorder produces abnormal hemoglobin which result in the red blood cells being crescent or sickle shaped, not round. These sickle-shaped blood cells become hard and sticky and have difficulty passing through small blood vessels and capillaries. They clog the flow and break apart. This is what causes the pain, damage and anemia.

Tay-Sachs Disease

This is a fatal disorder that most often occurs in members of the East European Jewish community. When born, the baby appears normal; but after six months the infant begins to develop mental retardation. This is followed by paralysis, blindness and seizures. Death usually occurs by the age of five or six.

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Gestational Diabetes (Diabetes of pregnancy)

You will have a one-hour glucola test between your 24th and 28th weeks of pregnancy to screen you for gestational diabetes. This type of diabetes can present serious health risks to you and your baby. This screening test will determine if you are at risk for gestational diabetes and if you need a more comprehensive 3-hour glucose tolerance test.

If you do have gestational diabetes as determined by the 3-hour test, you will be referred to a special program that helps you with your diet so that your sugar levels remain normal throughout the remainder of your pregnancy.

Preparing for the one-hour test:

1. On the day of your test, eat light, well-balanced meals. Avoid concentrated sweets. DO NOT EAT OR DRINK ANYTHING for two hours before the test.
2. At our office SIGN IN AT THE LAB. Since this will take an hour to complete, please arrive before 10:30 AM in the morning and before 3:30 PM in the afternoon.
3. The lab tech will give you a sweet drink called “glucola”. Exactly one hour after you drink the glucola your blood will be drawn.
4. Do not eat, drink, smoke or chew gum during this hour. Keep your activity to a minimum during the test.

We will contact you if the results of the test show a need for additional testing.

Preparing for the three-hour glucose tolerance test:

1. Eat your normal meals on the days leading up to the test. FAST FOR 12 HOURS BEFORE YOUR MORNING APPOINTMENT. Sips of water only.
2. At our office SIGN IN AT THE LAB for this morning test. It will take three hours to complete.
3. The lab tech will take a blood sample before giving you the “glucola” to drink. Your blood will be drawn three additional times; at 1 hour, at 2 hours and finally at 3 hours
4. Do not eat, drink, smoke or chew gum during the test. You may want to bring a book or something else to help you pass the time. Keep your activity to a minimum during the test.

We will contact you if the results of the test and advise you of the next step.

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Group B Strep

Group B Strep is a type of bacteria that is normally found in the vagina and/or rectum of some women. It is not a sexually transmitted disease. It can, however, in some cases cause serious infections to the newborn baby as it passes through the birth canal. We will order this test in the 35th or 36th week of pregnancy. If the test is positive, meaning that the Group B Strep bacteria is present, IV antibiotics will be started when you are admitted to the hospital for the delivery to help prevent this infection in the newborn.

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Non-Stress Test

Why am I having a Non-Stress Test?

Your doctor or midwife may recommend that you have a non-stress test during the later stages of your pregnancy. There are a number of reasons why this test may be ordered.

• High blood pressure or diabetes
• If your baby seems to be moving less than usual
• If you are past your scheduled due date
• If you’ve had difficulties/complications in one of your earlier pregnancies
• If both of us want reassurance that your baby is doing well

What exactly is a Non-Stress Test?

It is a safe, easy and painless way to check on your baby’s well-being before it is born. This test normally takes between 20 and 40 minutes to perform, depending on the activity and sleep pattern of the unborn baby. Two small monitors are placed on your abdomen and attached to an electronic measuring device. One of the monitors will measure your contractions while the other one will monitor baby’s heart rate. The evaluation of these two activities will help the provider evaluate baby’s condition.

Based on this evaluation, you may be sent home with detailed instructions on what to do over the next period of time. You may also be admitted for the health of you and the baby.

Is there any other testing to be done like this?

Your doctor may request that an AFI and a BPP be done. An ultrasound is done to determine the amount of amniotic fluid that surrounds your baby. This Amniotic Fluid Index will tell the physician if the baby and placenta are making enough fluid. Additionally , a BioPhysical Profile, consisting of the NST, the AFI, and observations of both baby’s arms/legs movement and large body movements (the chest muscles, which are a reflection of baby’s ability to breathe) will tell the physician whether the circulation to the baby is adequate.