Risk of Amniocentesis
Friday, April 27, 2007
Kenneth F. Trofatter, Jr., MD, PhD
The first amniocentesis for chromosomal analysis of cultured fetal cells from amniotic fluid was described in a brief article by Steele and Breg in 1966 (Lancet 1966;1:383-5). Ten years earlier, Fuchs and Riis (Nature 1956;177:330) had reported doing the procedure just for fetal sex determination. In both instances, these procedures were done ‘blindly’ inserting a needle without any method of direct visualization into the uterine cavity.
When I started my OB/GYN residency in 1979, our technique was barely better. We sent the pregnant woman to ultrasound (static), a fluid ‘pocket’ was identified, an “X” was placed on her abdomen at the “best place to stick a needle,” she was sent back to our clinic, and we BLINDLY placed an 18 gauge (large bore) needle into the uterus at the site of the “X.” It was not at all unusual to meet some resistance (some part of the baby – never felt real comfortable about that) or draw back blood (from the placenta, umbilical cord, or uterine blood vessels) before finally getting the fluid we needed to do the fetal chromosomal studies.
Despite the relative crudeness of this approach, the chance of losing the baby after this procedure was only about 1 in 200, and that has been the number routinely quoted to women for the “risk” of amniocentesis over the past 30 years, even though we now do these procedures using direct, real-time ultrasound guidance and a thin, usually, 22 gauge needle. Most of us who have done lots of these over the years (I put my numbers somewhere between 5 and 10,000) have known the risk is much lower. In fact, I only know one woman who lost a baby following an amniocentesis I have performed in the past 25 years (KNOCK ON WOOD), and she was probably well on the way to losing that pregnancy due to other complications. Anyway, it has been my routine for awhile to tell most women who come for amniocentesis that the “quoted risk is 1 in 200” but my “undocumented risk is less than 1 in 1000. Besides, I stayed at a Holiday Inn Express last night.”
Finally, as the result of a very large study that included documentation of outcomes following midtrimester amniocentesis, we have data to support the relative ‘safety’ of this procedure. In this study, the FASTER (First And Second Trimester Evaluation of Risk for aneuploidy) trial, the 3,096 women who underwent midtrimester amniocentesis (at many different institutions) were compared to 31,907 who did not (Eddleman, et al., Obstet Gynecol 2006;108:1067-72). The spontaneous fetal loss rate at less than 24 weeks following amniocentesis was 1.0% compared to the background loss rate in the control group of 0.94%. Therefore, the added risk of the amniocentesis was calculated to be only 0.06% (1.0% minus 0.94%) making the risk of the amniocentesis approximately 1 in 1600 – far less than the 1 in 200 (0.5%) risk that is usually quoted.
This information was presented to our patient today, but she was still very anxious about the prospects of the procedure. I told her that we saw no abnormalities of the baby at this time and that alone reduced her “age alone midtrimester risks” of 1 in 100 for Down syndrome (trisomy 21) and 1 in 51 risk for all chromosomal abnormalities by at least 50%. So, I offered her another option. “Why don’t you have a ‘quad screen’ (maternal serum screen) done today as a more reliable estimate of risk than that based on age alone. We will have the results back within 10 days, and you can use that information to further guide your decision regarding amniocentesis.” I then told her, that “because the odds were still in your favor that the baby is chromosomally ‘normal’, I am just going to schedule you for a ‘genetic sonogram’ at 18-19 weeks, and if the ‘quad screen’ results are scary, or if you just change your mind about the amniocentesis, we can see you back sooner and on very short notice.” She seemed happy with that plan…and it was the right decision for her at this time...so, I have a new friend!
143 Comments:
At Sun May 13, 08:21:00 PM 2007,
clacla said…
When i was pregnant with my daughter, i was told there was a 50% chance she would be disabled and posibly brain damaged when she wass born and i wa firstly told i should think very hard about aborting the baby before i got any further with the pregnancy.I also got advied to have an amniocentesis. To be honest though i knew there was nothing wrong with my baby, call it mothers instint or jut a bad call by the doctor involved i knew it was the right deicion for me not to do anything, and i had a healthy baby girl with absolutely nothing wrong.
At Wed May 16, 06:16:00 AM 2007,
Kenneth F. Trofatter, Jr., MD, PhD said…
I am glad things turned out okay. I am curious as to why your doctors thought there was such a high chnace that your baby woulsd have a problem?
At Sun Jul 29, 03:10:00 AM 2007,
Thea said…
I have sent a reaction before, but probably on the wrong page. What I wrote was in summary: can I come to your university and let an amniocentesis perform by you? I'm a Dutch woman aged 31 years and have had a "positive" result on the triple test of 1:5. I'm afraid of the risk of losing a healthy baby when doing an amniocentesis.
Thanks for responding. My email: teetje11@kpnplanet.nl
At Mon Jul 30, 10:15:00 AM 2007,
Kenneth F. Trofatter, Jr., MD, PhD said…
Thea,
If you live in the Netherlands, I recommend you find a doctor there to do the procedure. It is not a difficult procedure and can be done very safely by someone who has plenty of experience anywhere in the world. With a 1 in 5 risk, I recommend you have it done as soon as possible and ask that they send FISH (fluorescent in situ hybridization) which should be able to give a result for the more common chromosomal abnormalities within 72 hours. Thanks for reading and good luck.
Regards,
Dr T
I sent a copy of this to your email address
At Fri Aug 03, 06:03:00 AM 2007,
T said…
Dear mister Trofatter. I have another question, hoping you can give me an answer to. My gynaecologist has made an appointment for me in Amsterdam. But now I'm scheduled for an amnio next week, when I'm just 14 weeks and 2 days pregnant. Isn't this too early? I've heard there is an increased risk doing the amnio before 15 weeks, is that correct? Thanks again for your time.
T
At Fri Aug 03, 05:00:00 PM 2007,
Kenneth F. Trofatter, Jr., MD, PhD said…
Hi Thea: Years ago I did many at 14-15 weeks and was fortunate never to have had any complications, but there is a greater risk of complications at 14 weeks and I usually do not offer them now until 15-16 weeks. I hope things turn out well for you. Please let me know the outcome. Dr T
At Fri Dec 07, 12:59:00 PM 2007,
Andy said…
Dear Dr. Trofatter:
I am 37 and this is my first pregnancy. I had a first trimester screening that came back with very good results according to my doctor (1/1200 for Down's, and 1/5000 for trisomy 18). I have two questions:
1)My husband and I are still evaluating if I should have an amniocentesis performed or if it's not worth the risk. Would you recommend against performing the amniocentesis?
2)My due date according to my last period is June 18th, but when my baby was dated by ultrasound I was told that my real due date is June 22, but they're sticking with June 18 as my due date. Is the due date taken into account when calculating the results of the first trimester screening? If so would this 3 day difference alter the results? (I'm afraid that the same NT measurment might not give the same probabilities for a baby 3days younger).
Thank you for your help!
At Fri Dec 14, 03:25:00 PM 2007,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Andy Dec 7: The 3 days should not make a difference. You have VERY reassuring first trimester screening results. We would ordinarily only recommend a MSAFP screen at 16 weeks and a 'targeted ultrasound' at 18-20 weeks under these circumstances. Such good results are the primary reason we have been able to reduce the number of invasive diagnostics studies we do. Inherantly, the risk of amniocentesis is low, but if you lose a baby with an amnio under these circumstances, it will more likely than not be a NORMAL baby. However, YOU are the patient and we NEVER tell you what you should do. The only questions to you are: Do you need/want to know and do you understand the risks to find out? We do not particularly care what you decide because we do not have to live with either the decision or the consequences! We just promise to do the procedure the best we know how. Hope that helps and thank you for reading. Dr T
At Thu Dec 20, 05:11:00 AM 2007,
mana said…
hi my names romana i am 30 and 15 weeks pre with my 3rd child , had acll frommidwife advising me that i am high risk accordinging to her notes of baby having downs synrome they are doing the blood test nxt week, can they tell if i am high risk without the tests carried out... i have no rev history or family history or prev pregnancy probs i am quite worried...
At Thu Dec 20, 03:26:00 PM 2007,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Romana Dec 20: I am confused. Why does your midwife think you are at "high risk" for having a baby with Down syndrome? Have you asked her? Something does not add up! Why don't you find out and get back to us. Thanks for reading. Dr T
At Thu Dec 27, 07:18:00 PM 2007,
Anonymous said…
dear dr. trofatter
im jehn,29yrs.old & im 23 wks.my doctor said that my baby had a bright spot on her heart that findings links to down syndrome.they did sonogram & turned out everything ok no markers of ds.but still i had genetic counselling they ask me if want to do a amiocentesis to confimed the ds.i had a history of misscarriage several years ago.this is my second pregnancy & i dont wanna loose it.please give me some advice
At Sat Jan 05, 12:10:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Jehn Dec 27: I am sorry it has taken so long to respond, but Healthline has had some 'technical difficulties' and I just received your question yesterday. The bright spot in your baby's heart is an echogenic intracardiac focus (EIF). It is SO WEAKLY associated with chromosomal abnormalities that at your age, at your gestational age, and in the absence of more signficant fetal abnormalities, I personally would NOT RECOMMEND the amniocentesis. If you cannot sleep without knowing, then have it done, but understand that if you lose the baby, or need to be delivered prematurely, as a result of the procedure, the overwhelming likelihood is that your baby is NORMAL. Dr T
At Tue Jan 22, 09:25:00 AM 2008,
Anonymous said…
Dr. T - I wrote to you a few months ago on your recurrent loss blog regarding my two 2007 1st trimester losses - I followed your advice to see a good RE, we found impaired glucose tolerance, I started metformin, and I am happy to report that I am 15 1/2 weeks pregnant with what seems to be a healthy baby! So, thanks for that.
Here's my new question: I just turned 39. I had a NT done, and my risk for Downs is 1/2000 and my risk for Trisomy 18 is 1/3700 - which is reassuring. I scheduled an amnio anyway, because I am 39, and because of the possibility of the chromosomal problems with my lost pregnancies last year. Now, I am a week away from the amnio, and I am getting paranoid about the risk from the amnio of losing this baby. What I don't quite understand is how a history of previous losses impacts the risk of amnio. Does it make a difference if your previous losses were not spontaneous miscarriages, but missed ones? I was ok with my decision to have an amnio until yesterday, and now I can't get past the thought that something bad might happen. I know that my doctor doesn't care either way if I do the test or not, but I don't want to talk myself out of (or into) something if I am being overly cautious. Thanks in advance.
Liz
At Tue Jan 22, 05:27:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Liz Jan 22: Liz, I am not going to tell you what to do. But, let me put this in perspective. The risk of the amniocentesis in experienced hands is still about twice that of your a priori risk for having a baby with Down syndrome or trisomy 18 (and probably several other chromosomal abnormalities as well). In less experienced hands, the amniocnetsis risk can be 10 times your first trimester screening risk! With those odds, if you did happen to be the 1 in 1000 (or 1 in 200) who lost their baby as the result of the amniocentesis, the overwhelming odds are that you will lose a completely NORMAL baby. You are doing very well, you have been through a lot to get to this point and you are 39 years old. You may not have many more opportunities. One option (rather than juming into the amniocentesis now) to consider is to simply have a genetic sonogram done at 18-20 weeks. If that is normal, your a priori risk (based on the first trimester screening results) is reduced another 50% at least (I generally quote folks 60-80%). If something really suspicious is seen at that point such as poor fetal growth, congenital heart defect, or a major marker for aneuploidy (and I am NOT talking about an echogenic intracardiac focus, or even a choroid plexus cyst alone), you could still opt for the amniocentesis with a FISH (fluorescent in situ hybridization) analysis for the more common types of chromosomal abnormalities. This can give you highly reliable results within 72 hours. Using first trimester screening, coupled with this approach, we have not missed a chromosmal abnormality in more than three years. By the way, CONGRATULATIONS! Again, best wishes to you and please let us know how you do with the pregnancy! Dr T
At Wed Jan 23, 01:44:00 PM 2008,
Anonymous said…
Dr. T,
We have recently found out that my 17 year old niece is pregnant and is not sure who the father is. She had her first OB/GYN appointment last week and the doctor first determined that her due date was August 25. After performing a sonogram he upped her due date to August 5. Now her boyfriend would like for her to have an amnio done to determine paternity. I would like to see them wait until birth to have paternity determined. What do you suggest?
At Thu Jan 24, 02:15:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Anonymous Jan 23: At this point the purported father of the baby has absolutely NO say in what your daughter does or does not do during this pregnancy. In many states (and you will have to check with yours), paternity testing is a big deal that requires legal representation on both sides and handling of blood samples from the mother, baby, and possible father in ways that rival a crime lab investigation because of the long-term implications of the results (support, etc.) that can be the end result. I do NOT recommend that she have an amniocentesis done for this reason alone. The testing is most reliably perfomed on blood samples and to sample the baby's blood from the umbilical cord in utero imposes some risk on the pregnancy. Now that your daughter knows how 'far along' she is, there is a very good chance she can be provided an approximate date of conception and will be in a position to tell you now if paternity is an issue. Good luck!
Dr T
At Sun Jan 27, 11:31:00 PM 2008,
Cass said…
Hello, Iam 25 years old, and on my 3rd pregnancy.. So far so good until I got the results of my triple quad screen and it was positive for Down's??? Iam scheduled for an Amnio on the 30th but Iam having second thoughts due to all the Miscarriages Iam reading about after the procedure... Just wondering what causes a miscarriage after the amnio and what are my chances of a miscarriage and my chances of having a baby with Down's??? Thanks Cassandra
At Mon Jan 28, 06:20:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Cassandra Jan 27: How high is your risk for Down syndrome based on the screening test? In very experienced hands the risk of an amniocentesis between 16 and 20 weeks is probably less than 1 in 1000. By "risk" we are talking about losing the baby as the result of the procedure as the consequence of rupturing membranes, introducing infection, or damage to the baby or placenta. Each of these complications are fairly uncommon. If your risk for Down syndrome is less than 1 in 100, you might consier simply having a 'genetic sonogram' done at 18-20 weeks (as I suggested to another reader in a recent post) and then deciding on the amniocentesis based on those findings. A normal ultrasound at that point reduces the risk based on your screening results by at least 60-80%. Good luck and let us know how things turn out. Dr T
At Sat Feb 09, 12:56:00 PM 2008,
Anonymous said…
Hello Doctor. I am 36, in my 14th week of pregnancy and am scheduled to have an amniocentesis in my 16th week. The decision to have the amnio was due to a miscarriage last summer that, when biopsied after D & E surgery, showed that I am a carrier of a balanced translocation. Do you think that it is a smart decision to have the amnio? Just searching for some objective professional reassurance.
At Wed Feb 13, 09:49:00 AM 2008,
Anonymous said…
Dear Dr. Trofatter:
I am 37 and this is my first pregnancy. I had a first trimester screening (including nuchal and hcg/PAPP-A) and the results were 1/1125 for Downs and 1/5000 for Trisomy 18/13. The nuchal (1.3) and hcg (0.97 MOM) number were great but the PAPP-A number was 0.54 MOM, which increased my overall risk. I had the 16 week AFP only screen and the number was 1.29 MOM which indicated 1/5000 (approx) risk for neural tube defects. I recently had a 20 week sonogram and they detected renal pyelestasis, which they told me was a soft marker for downs and doubled my risk. I guess my risk is approx 1/550 now. This was the only marker they saw and the rest of the sonogram was normal. I am nervous about having an amnio because of the risk of losing a healthy baby. I would appreciate your thoughts.
At Thu Feb 14, 08:50:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To anonymous Feb 9: What balanced translocation do you carry? Even though you have gotten this far, thereby reducing your risk that the baby has aneuploidy (too much or too little genetic material), an amniocentesis is probably prudent. Some balanced translocations can result in subtle chromosomal aabnormalities that are often just as devastating to the baby in the long run. Good luck to you and please let us know what you find out! Dr T
At Fri Feb 15, 05:03:00 AM 2008,
Anonymous said…
Hi Doctor Trofatter. Thank you for your post. I have a non-Robinsonian balanced translocation between chromosomes 3 and 20. Thanks in advance for any insight. ~Christen (previously Anonymous
At Fri Feb 15, 10:26:00 AM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To anonymous Feb 13: If all they saw was mild pyelectasis, I would not generally recommend an amniocentesis with the a priori risk you have based on the first trimester screen. But it is still your choice in the end. My suggestion would be to relax, odds are your baby is chromosomally normal! Let us know how things turn out. Dr T
At Fri Feb 22, 06:47:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Christen: The odds are in your favor that the baby has either a normal karyotype or is also a balnaced translocation carrier. We would still offer you an amniocentesis to find out for sure, but with aneuploidy for either chromosome 3 or 20, there is a very good chance you would not have carried this far into the pregnancy. That's why I believe your odds are good that this baby is 'normal'. Best wishes and let us know what you do and how things turn out! Dr T
At Sat Feb 23, 07:27:00 AM 2008,
Anonymous said…
Hi Dr. Trofatter,
My 1st trimester screening increased my odds from 1:172 to 1:126. I will be 38.9 years old on my due date. My results were 2.5mm NT (1.54 MoM), free beta HCG 1.55 MoM and my PAPP A was .81 MoM. My 20 week scan found only a RT pelvis borderline dilation of 4.5 mm and my risk was increased to 1:85. I am really scared and struggling with what to do. I have a history of 3 spontenous misscariages before 12 weeks. I am currently 21 weeks and my amnio is scheduled for Monday. I have no children. Your thoughts would be much appreciated.
At Thu Feb 28, 04:46:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To anaonymous Feb 23: If the only 'abnormality' your doctors saw was a slightly dilated renal pelvis, the odds are still in your favor that the baby is chromosomally normal. You have to ask yourself how badly you need to know before you deliver. The risk of the amniocentesis is probably only a tenth the risk of your having a baby with Down syndrome, but with the odds you quoted to me, if you did happen to lose the baby, and the loss was related to the amniocentesis, the odds are that you would actually lose a chromosomally normal baby. I also hate to raise this issue, but my other question is related to the fact that you are having an amnio a little late in the pregnancy. Do you have any idea what your plans would be if you actually did find out the baby had Down syndrome. The answers are not easy and you have to make a decsion that is right for you. Please let us know what you decide and how things turn out. Best of luck! Dr T
At Sun Mar 16, 07:46:00 PM 2008,
Anonymous said…
Dr. Trofatter..I posted a comment back in February. (Refer to Christen's posts) I was supposed to have the amnio three weeks ago but my husband and I decided against it at the time- ambivilant overall. The ultrasound that day showed everything to be normal- everything that an ultrasound can pick up anyway (structure/organs). We now have another ultrasound/amnio (<-possibly) scheduled this Tuesday the 18th, which will be week 19. I go back and forth about it- don't want to be the 0.5% that has that miscarriage due to the amnio... but just wanted to know from you- is there any greater benefit to waiting the extra three weeks? i.e. more amniotic fluid. I really want to get it- I just want to have assurance that it's the right choice. Thanks again, Christen
At Wed Mar 19, 11:23:00 AM 2008,
Anonymous said…
Hi Dr. Trofatter,
I’m 38 and 18 weeks along. This is my 3d child. (I had my last one 8 years ago.) I’ve also had two miscarriages. I don’t know what my risks are – I didn’t even know there was a first trimester screening. My doctor just asked if I was considering amnio, then he referred me to a specialist. I see the amnio guy in a couple of days. I did ask to have an AFP at my last doctor’s visit (about a week ago). The doctor told me that the office doesn’t call with results unless there’s bad news, and I haven’t heard anything, so I guess it’s either good news or the results aren’t in yet. I’m someone who would consider terminating the pregnancy if a problem arose, but I don’t want to lose a baby just because I made the selfish decision to check its chromosomes. Can I ask the amnio doctor for a genetic sonogram, or is that a different doctor? And should I feel pretty confident if those results come back normal? I’m worrying myself sick about this. Chromosomal problems don’t run on either side of the family, but I’m also the oldest one to have a baby…
Any advice would be greatly appreciated. Thanks in advance.
At Thu Mar 20, 07:21:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Christen Mar 16: Sorry, I did not see your note until today. An amnio is easier in later pregnancy (usually) because there is more fluid. In experienced hands, the risk of an amnio shuld be much less than 0.5%. Incidentally, a targeted ultrasound at 18-20 weeks, if all is 'normal', should also reduce your age alone risk by at least 60-80%, essentially to less than that of a 35 year old woman. Your negative family history has very little impact on your age alone risk for aneuploidy. Please let us know what you decided and how things turn out. Best wishes. Dr T
At Fri Mar 21, 05:33:00 PM 2008,
Anonymous said…
Hi Doctor Trofatter. It's Christen. I ended up not getting the amnio on Tuesday. I received results from the targeted ultrasound that were deemed "normal" and with the doc's exceptional knowledge of spurting statitics at me, we felt very good about opting out of the amnio. We know that it doesn't rule everything out but couldn't justify taking the risk, be it minute. For some reason, we were thinking the amnio might be able to tell us more about MR (mental retardation)- it's a fear of mine- and the doc said that it wouldn't be able to tell us anything so it solidified our decision to pass on the procedure. Thanks for your post even thought it was after the fact. My post was last minute anyway. Again- thank you for your words. ~Christen
At Wed Mar 26, 06:21:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
Christen: Thanks for the kind words. I think you have made the right decision for you and that is SO important. Stay in touch, okay!?! Dr T
At Sat Apr 12, 07:15:00 AM 2008,
Anonymous said…
I am thinking of getting an amnio on either monday or tuesday (4/14 or 4/15) if they can get me in but I am so scared. I am afraid to miscarry like everyone else but especially because I had some first trimeater bleeding..not much just a couple days in week 5(too late for implantation bleeding so who knows what caused that) My quad screen came back negative but I am 40 years old. I would terminate for down syndrome however I am afraid to lose a healthy baby at this point. Is the amnio safe at 20 weeks or 21 weeks and is it worth doing at this point. I am so afraid that the dates might not have been accurate on the quad screen. I know my dates for sure and I was 15 1/2 weeks when it was done but the baby measured 16 weeks and 4 days and my doctor has my due dated at 9/3. Shouldn't my due date from LMP of 11/25 be 9/1 or 8/31(leap year). Would any of this make a difference on the quad screen results leading me to believe that everything looked ok when maybe it does not??? Also the nuchal was negative and my 19 week targeted ultrasound showed nothing.
I cannot seem to make a decision that I am comfortable with. My doctor is on vacation and honestly they just don't seem open to my many questions regarding this life altering decision.
At Sat Apr 12, 07:40:00 AM 2008,
Anonymous said…
i live in ny and would like for you to do my amnio. is that possible? i would like someone who actually cares about the women going through this and i cannot find that here in syracuse, ny. maybe i have waited too long because i am 20 weeks tomorrow but i have not found the right person to do such am important test up here.
At Tue Apr 15, 04:25:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To anonymous Apr 12: Sorry for the delay in my response, but I have been out of town. If you have negative 'screening' to this point, that means you are below the risk of a 35 year old woman for having a baby with Down syndrome or trisomies 18 or 13! That ain't bad for a 40 year old because your age factors so much into the risk assessment. In the end the choice is entirely yours because you must live with the decision. However, if the ultrasound is 'normal' then that reduces your risk at least another 60-80%! Remember, if you are at "low risk" and have an amnio done and then lose the baby as the result of the procedure, the odds are that you would be losing a chromosomally NORMAL baby under these circumstances. However, if you can't get through the rest of the pregnancy without knowing for sure, then the right choice for you might be to have it done. Think about these things and let us know what you decide and how things turn out. I am betting you have a normal baby myself! Dr T
At Tue Apr 15, 04:28:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To anonymous in NY: I am flattered that you would ask, but there are many very good doctors between Greenville,SC and Syracuse who have plenty of experience. Why were you going to have the amnio done? Is there a local specialist in Maternal-Fetal Medicine with whom your doctor consults? Best of luck to you and please stay in touch. Dr T
At Sat Apr 26, 03:02:00 AM 2008,
Anonymous said…
Dear Doctor Trofatter
My name is Michelle and I am desperate for a response. I have just turned 39 and am 14 weeks pregnant. I had the first trimester scan 2 days ago and they told me that I was a low risk for having a baby with Down Syndrome. My result from the ultrasound was 1 in 340. I just cried and cried. I have a 3 year old daughter and when I had the first trimester ultrasound then, the result was 1 in 2138. They told me that I should not compare this result to the previous one, because I am 3 1/2 years older. I have made a tentative booking for the 6th May to have the amniocentesis test, but I am terrified and don't know what to do. I am desperate for some advice
At Mon Apr 28, 12:10:00 PM 2008,
Michelle said…
Dear Dr. T.,
I just got back my results from the second blood draw in stepwise sequential screening. I am 33 and a normal screening for someone my age would read 1/405 for downs. The results from my first draw were 1 out of 152 for downs and 1 out of 101 from the second draw. My husband and I had agreed that if the risk went up tremendously we would consider doing an amnio; however, a risk of 1 and 101 is still very small. However, I am concerned that my risk has kept on increasing. I also know that the risk of amniocentesis is very small - even smaller than the typical quote of 1o ut of 200, but I'm still very hesitant to have one done. Based off of my risk assessment, how would you advise a patient how to proceed. I do not know what we would do if we were given a diagnosis of a downs baby.
At Wed Apr 30, 02:21:00 PM 2008,
Michele S. said…
Dear Dr. T,
I hope you can give me your opinion. I am 13 weeks pregant (from IVF), 41 years old, and will be 42 on my due date of 11/5/2008. I previously had a miscarriage at 11 weeks due to Trisomy 15 two years ago. This will be my first baby.
My 1st trimester screen was normal, the nuchal test was 1.21 and the other tests showed 1/1000 for Downs and 1/5000 for Trisomy 18. I am scheduled for an amnio on May 19th. Now I'm torn as to whether I still have a need for it. I do have a first cousin with mental retardation in the family and also an autisic first cousin. Please let me know your thoughts.
Thanks, Michele S.
At Wed Apr 30, 06:18:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Michelle Apr 26: Let's put this in perspective. Your calculated risk is about one-third your age alone risk and you have a 339 out of 340 (99.7%) chance that your baby does NOT have Down syndrome. I would think long and hard about having the amniocentesis done at your age without more evidence that the baby ccould have Down syndrome. You are not getting any younger and a 'normal' genetic ultrasound will reduce your risk at least another 60-80%. The choice in the end is yours, but I want you to think about what I have said! Good luck and please let us know how things turn out. Dr T
At Wed Apr 30, 06:21:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Michele S: At your age and with those results, the likelihood that the baby has Down syndrome is extraordinarily LOW and the risk of the amnio gretaer than the risk of Down's. There are other chromosomal abnormalities that are not detected by the screening tests, but you might consider simply having a good genetic ultrasound done before making the final decision regarding the amniocentesis. Good luck and let us know how things turn out. Dr T
At Thu May 01, 06:07:00 AM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Michelle Apr 28: My goodness, the last 3-4 comments on this post are from Michelles, I hope I am not getting all of you confused with my answers. Anyway, in your case, the risk of 1 in 100 is relatively high. You have sevral options: you can await a good genetic sonogram and then make a final decision regarding amniocentesis based on those findings (a normal study reduces you a priori risk by at least 60-80%) or you can proceed with an amniocentesis. I cannot tell you what to do, but if you really are someone who just needs more information, i.e., you "don't know what you would do", sometimes it is better to get that information and the amnio is a relatively safe way to do that. In reality, MOST folks don't know what they do until they have a diagnosis in hand and sometimes their final decisions surprise even them! Good luck with things and let us know what you choose to do regarding the amnio and what you find out. Dr T
At Tue May 06, 12:26:00 AM 2008,
katie said…
Hi Doctor
I am just 14 weeks pregnant and I just received my results from my ultra screen today. My results were 1/10,000 for Down's but a scary 1/173 for Trisomy 18 and 13. I am 30 and this is my first pregnancy. I really want to know but I am scared of miscarrying a healthy baby. I have PCOS and only had 3 periods last year and this baby is very much wanted. I have thought about waiting for the targeted ultrasound but I am worried that if tat is not encouraging that I will have to make a difficult decision when I am much more pregnant. Is it ok to go ahead with the amnio now or would you advise me waiting for a few more weeks (what is ideal)if that is what I decide to do? Thanks so much
At Tue May 06, 02:48:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Katie May 6: If you have the amnio done, I would wait until closer to 16 weeks to minimize risks. Quite frankly, the odds are that the baby does NOT have trisomy 18 or 13 and most babies with either of those chromosomal abnormalities usually have multiple physical defects, many of which may be visible by 16 weeks. In the end the choice is yours, but with your medical history, I would lean toward the least invasive approach to help you make the final decision regarding the amnio. Best wishes and let us know what happens. Dr T
At Tue May 06, 11:03:00 PM 2008,
katie said…
Thank you so much for your response. I really apprecaite it as I think you have also been sick recently. I hope you are feeling better now.
I also wrote a message on the page about low PAPP-A. I called my doctor and got the figures from them. I also talked to my perinatologist today and she advised I have an ultrasound at 17 weeks and a possible amnio straight after that if the results look in any way concerning.
I am afriad that I have a few other questions
1)Given my low PAPP-A (0.42) and low HcG (0.29)do you think there are other chromosonal problems that the ultrascreen does not detect that are likely?
Maybe it will be useful to know that I am 30, with a BMI of 21, non smoker and non drinker and pretty physically active. My NT was 0.7 and the nasal bone was present in the scan. Also growth of the baby so far looks good.
2) How low are these results really? I cant seem to find information on what is considered a "normal" range for HcG and PAPP-A
3) IS it a good idea to get the AFP test or might that only confuse things and make me more worried?
3) Given my blood tests results are there other things I should be immediately concerned about, such as low amnio fluid or placental problems?
Your response is very helpful I was really hysterical yesterday but hopefully with help from your board I will get through this bad time and so will veryone else. I have a count down until the 27th of May for the ultrasound.
At Fri May 09, 07:42:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Katie May 6: 1) There could be other chromsomal abnormalities that are not effectively detected by the ultrascreen, there could be an abnormality of placentation, or there could be absolutely nothing wrong.
2) Both the hCG and the PAPP-A values are below the 5th percentile for the MoM at he gestational age at which they were performed
3) I would recommend the AFP test alone (not the full 'quad screen') because it may give us some early indication that the placenta is not as healthy as it should be, putting you at risk for poor fetal growth, hypertensive disorders of pregnancy, and need for early delivery.
4) At this point, I do not think there is anything you need to be IMMEDIATELY concerned about. Your baby is normally grown and that is a very good sign. Your doctors will probably continue to follow the baby's growth and at some point perform Doppler studies to assess whether you or the baby are having trouble pushing blood through the placenta. Let them explain that one to you!
Good luck Katie, relax a bit, and let us know how things turn out. Dr T
At Mon May 12, 08:29:00 AM 2008,
katie said…
Dear Dr T
Many thanks for your response. I will see my OB tomorrow for my regular check up and I will ask her about the AFP and some other things. I will let you know how I get on.
I guess my main question from your reponse would be what other possible chromosmal problems could my results indiate, and would the amnio or a level II ultrascreen be able to tell me more?
Thanks so much for your advice and support.
At Mon May 12, 09:54:00 PM 2008,
Anonymous said…
I am 37 yrs old and this is my first pregnancy, 19 wks, and although ultrasounds at 12 and 18 wk all normal I am having amnio tomorrow based on HCG 79,988 mIU/ml (1.54 mom) and risk estimated based on 1) age alone 1:242 and 2) 15 weeks 1:56. I'm told I will have to wait 3 weeks for results and I would appreciate your interpretation of my risk with these results?
At Tue May 13, 06:15:00 AM 2008,
dawnmarie1again said…
Dear Dr. T.,
I'm 35 and currently pregnant with my 3rd child. I have 2 very healthy girls that are age 11 and 4. My third trimester screening with bloodwork came back with a 1/483 chance of having a baby with DS and a 1/10,000+ chance of trisomy.
However, last week (21 weeks and 5 days) I went for my genetic ultrasound. They said that the baby had mild pyelectasis (1 very mild enlarged kidney) and bright bowel which are soft markers for down syndrome. They said that everything else was measuring to the day and the heart, nasal bone, femur, etc. were all looking perfect. They have confirmed that the baby is a boy which could explain the enlarged kidney because it's more common to happen in boys because their "plumbing" is longer.
Based on those 2 soft markers and my age of 35, they drastically changed my chances to 1/13 of having a baby with DS. My husband and I decided that we are going to have the baby regardless, however I haven't had a good night of sleep since. I believe I still have a 93% chance of having a perfect baby. Is my fear of the amnio wrong? I just don't want to loose a healthy baby because of my decision to have an amnio done.
If I did decide to have it later on just to know, what is the latest it can be performed?
At Tue May 13, 12:10:00 PM 2008,
Katie said…
Dear Dr T
Sorry it is Katie again.
I went to see my OB today and she was very nice and gave me time and assured me I had picked a great perinatologist. I also have an appointment with a genetic counselor tomorrow which might help also.
I have a few more questions I am afraid. I am really trying to avoid the Amnio because of the fear of complications but I am terrified of going to term with a baby with T13 or T18. I also forgot to mention that I have a liver adenoma that is being watched carefully and going to term anyway might have problems.
I want to know more about the ultrasound I will have on the 27th.
1) Should the ultrasound be 3d or just a high resolution ultrasound? Is there anything I should check in regards to quality of the instrument they have?
2) Is it possible to see malformations for both T13 and T18? I hear that T13 malformations can be harder to spot???
3) Is it possible to see malformations if it is T13 T 18 or T21 mosaicism???
4) Finally, if I have an amnio are there any ways to reduce the risk of infection.? When I asked about miscarriages at the facility I am going to (Atlanta Perinatologist) they told me most seemed to be related to infection. Is this due to the sterility of the equipment or the room used???? Is there anything I can do about this?
Many thanks again for your consideration
At Tue May 13, 05:42:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Katie: The amnio is of course the way to definitively make the diagnosis of a fetal chromosomal abnormality. At least 60-80% of Down syndrome and more than 90% of trisomies 18 and 13 will be detected (at least suspected) by ultrasound abnormalities. Certain chromosomal abnormalities are very difficult to pick up by ultrasound and, particularly, the sex chromosomal abnormalities where the babies hav an extra X or Y chromosome. Some of these will result in positive first trimester screens. You should probably discuss these with your genetic counselor as you weigh your decisions regarding invasive testing. Godd luck again! Dr T
At Thu May 15, 06:33:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Katie: Almost all high resolution ultrasound equipment has 3D/4D capability these days. If your doctor is supicious of a fetal abnormality that might be better confirmed by 3D, they will most certainly do it; and, even if they don't suspect any problems, they will probably give you some pretty pictures of your baby.
T13 and T18 babies usually have many abnormalities and they usually have some degree of 'growth restriction' by midtrimester. They are not oftenn missed, even if a problem isn't suspected to begin with. Mosaicisms depend on how much the baby is affected (what percentage of cells and what organs are involved) so they can be a little tougher. However, again most of these babies will express the phenotype of the trisomy and the baby will have visible abnormalities.
Don't take anything yourself to try to reduce risk for infection. It is still a rare occurrence with amniocentesis. If you express your conscerns to your doctor, I am sure the most they would recommend is that you shower with a surgical prep such as Hibiclens before the procedure. I NEVER treat a patient with antibiotics when performing an amnio and haven't had an infection in over 20 years (knock on wood). Good luck and PLEASE try to relax, Girl! Dr T
At Thu May 15, 06:43:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To dawnmarie: I am sorry, but I would not have increased your risk at all (using the 1 in 483 as your a priori risk and NOT your age) for the unilateral 'pyelectasis.' And, there are many causes of echogenic bowel, the most common being an over call by the sonographer. I am not trying to practice medicine from a distance, but the odds are that this baby does NOT have Down syndrome, despite the 1 in 13 risk you have been quoted. Technically, you can have an amnio ANY time in pregnancy to find out if the baby has a chromosomal problem, but termination of pregnancy is dictated by your state's regulation. You are getting a little late in the game to consider that. I wish you luck, and please let me know how things turn out and if I have given you poor counsel. Dr T
At Thu May 29, 11:09:00 AM 2008,
katie said…
Dear Dr T
I just wanted to give you an update on my situation. I went for my appointment on the 27th and the U/S overall looked good. They said that they saw a ouple of Chorid pleuxs cycts but that was pretty common in normal babies. The felt I was too anxious though and that an amnio might be the only way to try and give me some peace of mind.
I wanted to know whether it is likely the baby would have T18 if the only sign was the cysts. Does it matter how many cysts they see? I was a little stressed so I didn't ask if there were any other markers visible. The cysts were the only ones mentioned when I pushed a bit.
I hope the results will only take 10 days. I opted not to get the FISH as I just want the final results.
Thanks so much (I am trying very hard to relax : )
Katie
PS I used the Hibiclens as mentioned in your previous entry to me
At Thu May 29, 06:26:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
Katie: EVERYTHING WILL BE FINE! Thanks for keeping us updated. Get some rest.
Dr T
At Thu Jun 05, 03:23:00 PM 2008,
Katie said…
Hi Dr T
I wanted to let you know that I got the results from the amnio back and the results were normal. I am incredibly relieved as you must imagine. Thanks again for all your support.
At Fri Jun 06, 05:57:00 PM 2008,
Anonymous said…
Dr. T.-
I'm 17 weeks pregnant and 34 years old. Early screening indicated a risk of 1/300, which my ob said was slightly above average for my age. On Monday I opted for the level II ultrasound and was told the baby had a white bladder and a spot on the heart, but that the spot on the heart was more of an indication for cystic fibrosis versus downs. I did the amnio and am going out of my mind waiting for the results. Is white bladder another sign of cystic fibrosis (dr. didn't mention this, but subsequent on-line research suggests that it it)? Can you tell me my risk factors for downs and cystic fibrosis based on these results?
At Sat Jun 07, 08:30:00 AM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Katie: Best of luck for the rest of the pregnancy! : )
Dr T
At Sat Jun 14, 10:54:00 AM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To anonymous June 6: I never heard of "white bladder" so I am not sure what that measn. Are you sure they didn't mean "echogenic" bowel. There is an association between echogenic (white-appearing)bowel and cystic fibrosis, congenital infections, and certain chromosomal abnormalities. However, that risk depends on the experience of the person interptreing the brightness of the bowel. In many cases this is an over call - in otherwords, it really isn't a problem. Have you yourself been screened for carrier status of cystic fibrosis? If you are NOT a carrier, it is very unlikely that the baby would have it. Since you had the amnio done, you should have the baby's chromosomal results back within a week. Let me know what that shows. I would be very surprised if it turned out your baby had Down syndrome. Best wishes! Dr T
At Mon Jun 16, 07:53:00 AM 2008,
Anonymous said…
I am 37 and 13 weeks pregnant. I have two children 4 and 7 and have had two miscarriages in the past two years. My first trimester screening, done at 12 weeks 2 days, indicated a 1 in 2,100 risk for DS and a 1 in 5,700 risk for Trisomy 18/13. I am still considering an amnio based on the high free beta hcg (mom) which was 2.34. Would this high level concern you? Thanks for your help. -Susan
At Mon Jun 16, 10:55:00 AM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Susan: The power of the screening test is in the COMBINATION of the results, not the individual values. I fully believe that, so at this point I cannot be overly concerned because of the hCG result alone! The risk of the amnio is significantly greater than the risk of having a baby with trisomy 21, 18, or 13 and if you were one of those unfortuante people who did lose a baby as the result of the amnio, odds are it would be a completely normal baby. Think about things in those terms! In the end, the final choice is yours, but in this situation I would be remiss if I did not play the "devil's advocate"! Best wishes and let us know how things turn out. Dr T
At Tue Jun 17, 10:21:00 AM 2008,
Alex said…
Dear Dr. Trofatter, I am really glad I found this blog article you wrote and was also able to read through the comments - very informative. I am currently in Germany and facing the prospect of getting my information from Doctors who speak a language I can understand only up to 80%. Which is why I've been looking online to try and find some more information. The question I have is how reliable is an amnio in diagnosing DS and the other chromosomal abnormalities it looks for? I've found accuracy figures of between 98% and 99.4%. These are the same sites that list a risk of miscarriage as being 1 in 100 or 1 in 200 (figures which from what I have been reading are out of date). In other words what I am asking is what are the chances of getting either a false negative or positive? Thank you in advance for any information you may have for me.
Regards, Alex
PS. And if by any chance you've heard of a good medical facility in Germany that carries out amnios (particularly in the south) I would be glad to find out about it...
At Tue Jun 17, 01:53:00 PM 2008,
Elsa said…
Dear Dr T.
I will be 35 in september and I am 14weeks pregnant, I got my results from the first screening as 1 in 169 for DS and the nuchal area was slightly enlarged at 2.7mm. (I was 13 weeks 1 day) How much can these results improve if we get a AFP test and detailed ultrasound? can it be worth waiting or is it a better idea to go ahead and get an amnio right away? Is there a risk number where you start recommending amnio? Also, how can I find the most qualified/experienced place for the amnio? Does the quality of the ultrasound system reduce the miscarriage risk? Thank you so much...
At Wed Jun 18, 06:56:00 AM 2008,
Anonymous said…
I am 36 years old and 18.3 weeks pregnant. I had the NT test done and the sonogram that indicated my risk of a ds baby was 1:3900. I had had the AFP test and my results were normal. When I went for my 18 week sonogram, they found an echogenic heart focus and a two vessel umbilical cord. Both of which they say are not related but my odds of a ds baby are now 1:2200. The number doesn't bother us as much as having 2 things on the sonogram that are not normal. I am a petite woman and the sonographer mentioned that sometimes things like the heart focus are seen in people like me because we are thinner and those things could exist in many other people. We are having genetic counseling appt tomorrow and have an appointment to have an amnio if we are still concerned. I have not slept since last Friday and have been worried since sonogram. How do you feel about the heart focus and umbilical cord? I am going to a high risk perinatal center for amnio - am I risking too much doing the amnio?
At Wed Jun 18, 07:31:00 AM 2008,
elsa said…
Hi Dr T,
I wrote the previous post (Elsa) and wanted to add some information that I just asked for regarding my first ultrasound ; The crown-Rump length was 71.3mm, NT 2.7mm, Free Beta 60th percentile, PappA 50th percentile. Thank you !
At Fri Jun 20, 07:32:00 PM 2008,
Karen said…
I just turned 40 and just got my amnio results called to me by the physician who performed the procedure. He said that the results were normal for a woman my age, and that the baby appears normal. Are there results that are different for an older woman as opposed to a younger woman?
Thank you for your time.
At Sat Jun 21, 05:27:00 PM 2008,
Kenneth F. Trofatter, Jr., MD, PhD said…
To Alex June 17: I have probbaly done 20,000+ amnios and I have never had a false positive and the only times the studies were not diagnostic was when the cells just did not grow for one reason or another (and there have not been but a couple of those over the years). Why is it that you are considering having an amnio done? Sorry, but I would not know who to refer you to in Germany. Wish I could help! Dr T