The vast majority of babies born are healthy, and there is not often a need for concern. However, some parents — and some caregivers — want to eliminate the worry of, various possible birth defects, such as chromosomal defects, birth defects from infection (including HIV and rubella) as well as defects caused by conditions such as fetal alcohol syndrome (aka FAS).
Many defects can be discovered during pregnancy via one or more prenatal tests. But how much you want to know is up to you. Some women feel routine testing is unnecessary in their cases, since the risk of serious defects for the majority of healthy and conscientious women is extremely small. They may also believe that a serious defect is likely to be discovered even without the test and don’t want to spend their pregnancy worrying too much about those that aren’t serious.
Some women say, “I would never terminate my pregnancy, regardless of the outcome of the testing, so I don’t want to do it.” And some fear an ambiguous result that may cause needless worry or the need for making frightening choices they feel are best left in the hands of a higher power.
Other parents feel better ruling out certain defects, especially those for which their baby is at higher risk; or perhaps they want advance notice of any issues, so they can prepare on both emotional and practical levels. For example, babies with certain defects may need to be delivered very carefully (sometimes via cesarean section, as a vaginal birth may be too traumatic) or may require special resuscitation equipment to be on hand at the time of birth.
If the birth defect is a very serious or potentially fatal one, knowing in advance may also help you, as a parent, to prepare emotionally for the situation your child faces. Having some time to know what to expect — and to accept — can allow the family of a child with a fatal defect to make the most of every moment.
First, don’t panic. Realize that a positive result does not necessarily mean that your baby has a neural tube defect or Down’s syndrome.
About 5% of the women screened will have a positive AFP result. Most women with a “screen positive” result will have normal healthy babies. The positive screening result simply indicates that there is an increased risk and further tests are indicated.Your caregiver will discuss your test results with you and will usually recommend an ultrasound and/or an amniocentesis, as well as a second AFP test.
Some neural tube defects can be partially corrected in utero using extremely high tech operative procedures. Other problems, however, are too severe to be compatible with life and will ultimately cause miscarriage or stillbirth.
Here’s what some moms-to-be have said about the test:
I will not terminate no matter what, so I don’t see the use. One of my friends say that they wanted to be prepared if they had a baby with defects, but I don’t understand what constitutes preparation. I mean, I wouldn’t buy a different crib or paint the walls a different color. The fact of knowing my child will have problems will devastate me now or later, so why not opt for later? I will still have the same love and care for him/her no matter what. I would go nuts worrying about a mentally retarded child now until the end of the pregnancy. I would rather save all my sanity for when I really need it — after my baby is born. – Tasha
I had the test with my first, even though nothing ran in our families and risk factors were really low, and regardless of the fact I knew I would keep my baby regardless. Thank God I did. My daughter had an abdominal wall defect called gastroschisis. I needed special doctors at a different hospital. It completely changed the course of pregnancy. We had it this time, but haven’t gotten the results back. We had an ultrasound and everything appeared fine, so I’m not worried, even if it comes back positive. – mandymay
I was really panicked when I got my AFP results. There were two levels that were ‘off’ with my blood… Nine days after we had the ultrasound done and the amniocentesis done we got news that our “little man” is just as perfect as he should be… all of his chromosomes were exactly as they should be — no extras… it was a roller coaster of emotions! – Laura
Hang in there. It’s not easy, but you will get an answer soon.
As you move into the trimester two, your caregiver will probably talk to you about the alpha fetoprotein test (also called the AFP test, triple marker screen, the triple test, expanded AFP or simply maternal serum screening). Ah yes, one more blood test.
Alpha fetoprotein is a substance made by the baby’s liver, and a small amount makes its way into the mother’s bloodstream and is therefore detectable with a blood test. The AFP test is conducted for the benefit of your baby, and the point is to evaluate the risk of certain birth defects, specifically:
- Down syndrome (Trisomy 21, in which there’s an extra copy of the 21st chromosome, causing mental retardation, developmental delays, possible heart defects and other problems).
- Neural tube defects (defects of the baby’s spine, head, and brain, such as spina bifida).
- Trisomy 18 (in which there’s an extra copy of the 18th chromosome, causing severe mental retardation and often other problems the baby may not survive).
Remember and understand: This is a screening test, not a diagnostic test — that is, this test will basically let you know if you’re at risk but will not provide a conclusive diagnosis. This is essential to understand, as there are a high number of “false positive” results with this test. This means that far more women are told their AFP test was positive (either meaning an atypically high score or low one) than actually are carrying a baby with a defect. However, that does not mean the AFP test is without value — this is simply a known limitation. This prenatal test still serves to help discover babies with certain defects.
For the AFP test, blood is drawn from the mom-to-be sometime between 15 and 20 weeks of pregnancy (13-18 weeks after conception). This test typically measures three substances present in the blood during pregnancy:
1. alpha-fetoprotein (AFP)
2. human chorionic gonadotropin (hCG)
3. unconjugated estriol (uE3)
To get the most accurate results — and to avoid any unnecessary follow-up tests — it’s best to be as certain as possible of the date of conception and/or the first day of your last menstrual period. If your dates are off, the blood levels of these substances will be off, and you are likely to get a false result.
Test results are also impacted by carrying more than one baby, your weight, age and ethnicity, or if you are diabetic. In twin and higher multiple pregnancies, AFP results are not reliable, because there is no way to determine the alpha fetoprotein levels from each separate baby.
