AFP Tests - What do they mean?

Pattie Hughes (7652) 21 Jun 2006 11:25 AM

False positive results are very common with the AFP. With my first pregnancy, the doctor suggested I skip the test since it is not very reliable. I didn't get it done. By the time I was pregnant with my second, that doctor had semi retired and wasn't delivering babies anymore. I had a new doctor who bullied me into taking the test. He said it was very reliable. I had a false positive and was told my baby may have Down's Syndrome. She didn't, but the stress it caused was enormous. I declined the test for my next two pregnancies.

Catherine Ipcizade (5617) 21 Jun 2006 11:49 AM

The test has a high false-positive rate when the numbers are LOW (indicative of Down Syndrome) BUT a very low false-positive rate when the numbers are HIGH (indicating spina bifida, acacephaly, etc.) I think the test is important. If you get a high result, often things can be done in utero to help the baby. Hard as it is though, it's every mother's decision....and not an easy one at that. If you do get a LOW false-positive, doctors often recommend an amnio, which my friend was told poses more risk of miscarriage than the possibility that your baby has Down Syndrome. Pregnancy is not easy. Neither is parenthood. Too bad we can't have crystal balls, huh?

Valorie Delp (49340) 22 Jun 2006 06:43 AM

I have also declined the test for my last two pregnancies. Many practices are now recommending a triple screen which is supposedly more reliable. I think the results are important depending on how the results determine your feelings regarding the pregnancy and baby. I didn't feel like the anxiety of a false positive was worth the potential ability to prepare for a special needs child. I have a friend who felt the exact opposite. She felt like she could prepare better if she knew for sure. But you're right Catherine, the chances of miscarrying with an amnio is slightly higher than the chances you'll have a down syndrome baby (depending on your own maternal factors like age, etc.). Many women are not aware, but if you are very concerned about down syndrome and don't want the amnio, a good perinatologist or technician can look for down syndrome on an ultra sound. (Level II or higher).

Catherine Ipcizade (5617) 22 Jun 2006 09:01 AM

In truth, I had the test not because of the risk of the LOW results, but because of the risk of the HIGH results. My best friend lost a baby due to anacephaly, which was detected with the HIGH results. I would never want to go through a pregnancy without knowing that my baby would not survive. If I could know, I would want to.

Pattie Hughes (7652) 22 Jun 2006 09:30 AM

I skipped the AFP, but had a level 2 ultrasound. This test is very accurate for diagnosing the problems that show up on the AFP. The level 2 will also show anecephaly or spina bifida and is much less invasive than an amnio. The AFP test is really just a screening test and not diagnostic. The doctor told me it helps them determine who should have further testing. The level 2 is best when done by a specialist in maternal fetal medicine.

Catherine Ipcizade (5617) 22 Jun 2006 09:55 AM

right-the AFP lets you know if you need to go for further testing; thus the phase 2 ultrasound. Usually you don't get one of these unless there is a possible problem.

Andrea M (2525) 23 Jun 2006 07:40 AM

I have had the AFP test done with all 3 of my pregnancies and for whatever reson the first 2 came back fine and my last one, with my daughter came back positive for Trisomy 18! If any of you know anything about this, it happens to be one of the worst! The baby most likely will not survive! I had a level III ultrasound done to see if she had this and they found out that she did not! Now I am not going to say that for the rest of the pregnancy that I wasn't scared to death, because I was! I didn't believe that she was ok, until I saw her! The one reason that they encourage me to have the test done is because my husband is adopted! I am not sure if I will have it done with the next pregnancy though!

Valorie Delp (49340) 23 Jun 2006 07:21 PM

I am also adopted and they said the same thing to me. But I still refuse to have it. I don't need to know.

mims1979 (5) 24 Sep 2006 08:53 PM

I'd like to share our story with you just to hopefully provide some advice and thoughts to help any of you through this time.

My wife and I, 27, our new parents to be and pretty much on this path alone because its been 10-15 years since there's been any babies around and a lot has changed. We were given a pamplet on amnio and AFP tests and asked if we wanted to do it. We agreed that we didn't want the amnio but would do the AFP in the hopes that if SB was found we could possibly do something to help the baby before it was born. We both are strong believers that this baby is a life rather its 2 seconds or 20 years old so terminating a pregnancy was never a thought or reason for wanting to take the test. Regardless of any of that we didn't put much if any thought into the test at all. My wife had blood drawn during another appt with her OB/Gyn and really never thought about it again. 3 days later a specialists' secretary 90 miles away from us called at 6:30 pm to schedule an appt for us. Couldn't tell us why we needed an appointment or anything. At that time it was too late in the day to get any answers so we both attempted to goto sleep that night with our minds racing trying to think of what could be wrong with our baby that requires us to visit a specialist. The next morning my wife is at the OB's office as it opens with questions. All that was told to her at that point is that because of the AFP results there is a chance our baby has downs. Thats basically it, no further details. So here we are on Wednesday with an appt 9am 90 miles away on Friday. My wife is too worried to even read about it. I on the other hand have to know everything about it. I've basically read everything about an AFP test that google could provide. On the inside my mind is racing with worry and with facts I have read on the internet etc. On the outside I'm doing my best for 2 days to act like I'm not worried at all trying to help my wife through this ordeal. We do not tell anyone the news because there is no reason in worrying anyone else. On Friday we are both at the Specialists office 30 minutes early. He is 1 hour late because he was caught up at the hospital. Finally we get called back and the US tech does a full diagnostic US. At this point I'm convinced that I know more about what I'm looking at than the tech does because of all the research I've done on downs before arriving. 10 minutes into the US and I'm 100% convinced that our baby is perfectly healthy and noone has told us anything at this point other than here's a leg, here's a stomach, here's a head, etc. 30 minutes later the Dr comes in and finishes out a last couple calculations and measurements and starts with all the details we should have been provided by our regular Dr in my opinion. He says that we were called over because our AFP test showed a 1 in 230 chance of having downs. During the US a lot of measurements were taken. 1 normal developement at this point(~17 wks) says a babies femur and humerus should be atleast 81% of the skulls size since downs effects long bone growth this can be a marker. All 4 heart chambers are developed and working fine. No liver or kidney dialation. Head is oval shapped as oppose to round. No stomach or intestinal potrusions or irregular coils. Skin behind the next was less than 6.5 mm thick. All of these can be soft markers for downs. Our baby possessed not one soft marker which the Dr confirms. At this point without going on an having an amnio and actually looking at our babies chromosomes he can't say 100% that there is no downs but he does change our chances to 1 in 1435. At this point we are offered amnio as an option. Option 2 is to come back atleast 3 weeks from not for another US to check growth rate. Option 3 is to do nothing. We choose to do nothing. The risk of 1 in 200 on amnio test loosing a baby isn't worth it to us. Option 2 seems like an over kill as there isn't even a hint or "close call" soft marker that our baby may have a problem. Limbs are nice and long, all parts a developed perfectly, even 2 days ahead developmentally. So we're happy with the result, leaving the appt with a feeling of dodging a 5 lb cannon ball to the chest as well as the knowledge that we have a beautiful 6 oz baby girl growing perfectly.

Now, having said all that, if infact we knew what we now know about AFP testing we would have never done the test. For one, its not even a "test". Its more of a "hunch" and from what I can find out its not a very good hunch at that especially in the case of downs predictions. I believe parents should 1, be given all the facts about false positive rates, normal chances, what AFP is, etc. 2, in the event an AFP test is scheduled, a US should be scheduled for the same day results are due so parents don't have to spend days worrying about this. I believe that if most parents were told the level of failures of this test, that AFP is completely normal in people whether pregnant, non-pregnant, male or female, Just because a mother's blood has high or low AFP doesn't mean there is a high or low value in the placenta, The fact that a positive (or negative for that matter) test result really doesn't mean much by itself, that a lot more mothers would choose not to do it. The worry and stress provided to us by this test wasn't worth it by our standard. As I said before, we had no desire to terminate a pregnancy under any circumstances so regardless of the outcome of this test I really don't know what we were expecting. I urge each of you to think about it long and hard before jumping into anything without full understanding. Do the research and know what you're getting into. Until you are provided with all the facts don't make a decision. For example, 1 in 1435 sounds like bad odds to me when we're talking about something like DS, but knowing that a normal female, same age, weight, race, etc has about a 1 in 1480 chance it doesn't sound so bad. For that matter, we probably had a better chance of being in a wreck and loosing the baby on the 180 mile round trip to find out that there was nothing wrong with the baby.

I won't pretend to know what is best for you and your situation, I hope our experience for one helps some of the other families with positive test results realize that 95% of the time, there's nothing wrong with your baby. And also try and provide a little more details than I could find before hand so you can know what to expect and look for. I thank God for our results and will pray for all your babies that they have the same outcome as us.