Scary quad screen - False Positive for Trisomy 18 and SLOS

So most of you that read this blog already know this story, as it happened a long time ago, and this blog is really to update family and friends. But I'm writing this anyway, mainly because when I went through this, I couldn't find a whole lot of info out there. And it was terrifying. And all the info I could find didn't apply to me very well. And all the stories I could find of people in a similar situation ended with a very sick baby. So I just feel like I should put my story out there. So here it goes.

Jason and I initially decided that we didn't want to go through any genetic screening tests. We knew that they weren't really diagnostic, that they really just gave you a ratio stating your chances of having a baby with various diseases. During the first trimester, this screening involves a level II ultrasound, several hours of your life, blood tests, and possibly a lot of expense...so that seemed like more of a pain than it was worth. Especially because the main disorder you hear about with these screenings is Downs Syndrome, and there are many happy Downs babies in this world. Also, if the tests do show an increased risk of something, the next step is an amnio, which carries a risk of miscarriage. In our heads, the worst case scenario was that the tests would show that we had say a 1 in 100 chance of having a Downs baby. Amnio's can carry somewhere around a 1 in 200 chance of miscarriage. So we knew that even if the tests did show an increased risk for Downs, we wouldn't risk an amnio. The benefit of knowing just didn't seem worth the risk. Plus, I'm 27. Not exactly a spring hen, but not anywhere close to the age where you really see increased risks of these things. Given all that, the genetic screening tests just didn't seem worth the hassle and worry.

But then I went to an appt by myself. And I was a little bit overwhelmed. And the midwife asked if I wanted this test, which was just a blood test...and since I already needed to have my blood drawn, it wouldn't even require an extra stick. And this test looked for neural tube defects, and I knew that with neural tube defects, a new baby can need a lot of corrective surgery... And the midwife made me feel like it was standard. So I caved. I let them test my blood. After all, it would cost me approximately 8 seconds, just the time it took to fill an extra tube. This was on a Friday, and I was 16 weeks along at this point.

The following Tuesday, Jason calls me at work around 6pm to let me know that he just checked our home voicemail, and that one of the nurses had called and asked me to call back. And that she'd actually called Monday, and he'd just gotten the message. She left her pager number. At first I couldn't figure out why a nurse was calling me. Then it dawned on me. It had to be about the screening. I ran through all the other options in my head, and none of them made sense. The nurse wouldn't call to reschedule an appt, or at least they hadn't the last time I'd had to have one rescheduled. The nice lady at the front desk did that. The other blood I'd had drawn was for a research study, and they weren't looking for anything in my blood that would warrant a phone call. I hadn't had any other tests done. What else could it be?

So I call the pager number over and over again. I have Jason try. But it's after hours. And I'm not having an emergency. I'm just going nuts. So it really wasn't appropriate to call the midwife or OB on call. They were probably doing important things like delivering babies. And Jason is convinced that I'm just worried about nothing, that they really are just calling to reschedule my next appointment. So after crying and worrying myself sick, I manage to calm down enough for the night.

Wednesday I get up as early as they open though and call the nurse. Finally I get through. And I was right, my screening had showed troubling results. But not for Downs or neural tube defects. My chance of having a baby with either of those was incredibly low. Instead, I showed increased risk for Smith-Lemli-Opitz Syndrome (SLOS) and also for Trisomy 18. The nurse though obviously isn't trained in genetic counseling though, and doesn't want to give me any extra info until I talk to the genetic counselor. I can't really blame her for that. What did suck though is that she actually gave me the WRONG info. She said I showed an increased risk for Trisomy 13. They don't actually screen for Trisomy 13 with the quad screen.

Anyway, she told me I should make an appointment for a level II ultrasound and a possible amnio for as soon as possible. So after some hassle, I got through to the people making the appointments. The first available thing they had was for that Friday afternoon...which meant I had to wait. The waiting was excruciating.

The nurse did give me enough info though that Jason and I could Google stuff for hours trying to figure out what the deal was. After some research, we assumed that what I heard as "smith lemon something or other" had to be SLOS, which is a genetic disease where the body can't make cholesterol, and causes mental retardation and other health problems. We researched Trisomy 13 as well, and found out that a diagnosis of Trisomy 13 would be devastating. Of the few babies that are born alive with Trisomy 13, very few survive the first year. We knew that they'd tested my blood, and the nurse said that one of the hormones they'd tested was AFP. What the nurse said beyond this, I couldn't remember by the time I got off the phone. I do know that after lots of research, we still weren't sure which test we'd had given all the info we knew.

Because I still felt clueless, I called the nurses back, feeling like an idiot, because I was supposed to be waiting until Friday to speak with the genetic counselor. I don't know if the nurse this time gave me wrong info or just worthless info. She told me that 10% of people have positive screening results, and only 2% of those people have babies with the disorder. She didn't know much beyond that. Her info was pretty much useless though because the majority of positive screening results are for Downs Syndrome, and you can't assume that because that statistic works overall, that it would work for each disease tested for.

So we researched and waited and cried until Friday afternoon came around. At this point we were continually researching Trisomy 13, as it was the worst case scenario. Every story we could find seemed to be about screening results for Downs Syndrome though. I know the people writing those posts were scared and that everybody wants their babies to be healthy, but I remember getting mad at them. I saw these posts and I thought that they didn't know how lucky they had it. If their babies did have Downs, at least they could be healthy and happy. If my baby had Trisomy 13, she might not even live an hour, if at all. Plus how much pain would she be in?

Finally Friday afternoon came, and we met with a very nice genetic counselor, who patiently answered all of our questions. Some things we already knew, but it was good to hear it explained more clearly anyway.

We learned right away that the test had NOT screened for Trisomy 13, and rather we had shown and increase risk for Trisomy 18. We were so relieved! Trisomy 18 can't be nearly so bad as Trisomy 13... But the genetic counselor gave us this funny look, and burst our bubble. Trisomy 18 is pretty much just as bad. If my baby did have Trisomy 18, many doctors wouldn't consider the pregnancy to be viable anymore. So right back to immensely worried we flew.

We learned that the blood test had been the quad screen, which tests for 4 different hormones in the blood. All 4 of my hormones had been lower than they should have been for my age, weight, and various other factors. This meant good things for the risk of Downs and neural tube defects...but my chances of having a baby with SLOS were greater than 1 in 50...and the chances of Trisomy 18 were greater than 1 in 15...and the lab we went through doesn't give out ratios higher than that; so it's basically the worst possible news at this point. We asked if those ratios were accurate in her experience, and she said yes.

We learned that less than 2% of women screen positive for Trisomy 18. The same is true for SLOS. And way less than 2% screen positive for both. That was why we had such a hard time finding info about our situation, and why stuff about Downs was everywhere to be found.

We learned that even though SLOS is a genetic disease which requires both parents to be carriers, that no test exists to check if Jason and I are carriers. We also learned that SLOS has a wider range of disability, meaning some people with SLOS are closer to the normal side of the scale while some aren't.

We learned that if our baby did have either of these diseases, that our likelihood of having another baby with the same diseases was increased (with SLOS, it goes to 1 in 4).

We learned that there are different kinds of Trisomy 18, and that this is a mutation that happens when the cells are multiplying. Depending on when the mutation occurs, some people have an extra chromosome 18 in all of their cells. Some people have this mutation in only some of their cells, meaning the mutation happened further along during development and only shows in cells descended from the mutated cell.

We learned that the ultrasound would give us a better idea of what was up, but that to truly know if our baby had either of these problems, we'd have to do an amnio. If we did the amnio, we'd get 3 rounds of results. The first round (the FISH results), would test for Trisomy 18 in a small sample of cells. So this test wouldn't necessarily show all variations of Trisomy 18 because the sample could be of healthy cells from an individual with both healthy and trimsomy cells. If all went well with the amnio, we'd get these results in about 3 days. The second round of results would be diagnostic for SLOS, and we'd get these results in about 7 days. The third round of results would test more cells for Trisomy 18, and should show as positive even if not all the cells have the mutation. These 3 tests are supposed to be 99.9% accurate.

We also learned that we could decide whether or not to do the amnio based on the ultrasound. If we opted not to do the amnio, we could do a follow-up ultrasound when she was a little bigger. If at 18 weeks the ultrasound looked perfect, the chance for Trisomy 18 drops to 1 in 150.

I'm sure there's more, but I think that's the gist of it...so at this point we went in for the level II ultrasound.

It was really cool to see her hands and feet and head, but we were so worried. The ultrasound tech was nice though and told us what she was looking at and whether or not it looked normal to her. Thankfully, we saw 4 chambers to her heart, which was a good sign. We also saw her clench and unclench her hands, and we saw 2 hemispheres to her brain. All good signs. What Jason and I didn't realize then is that she was measuring small. And small is not a good sign. It's actually a symptom of both Trisomy 18 and SLOS.

So after the ultrasound was over, we went back to the genetic counselor and learned that the ultrasound was inconclusive because of how small she was. Apparently, because she was small, they couldn't see all the markers they were looking for, or at least as clearly as they'd like. Also her size was a red flag (she was 10 days behind at this point.) With Downs and some of the other disorders, they recommend retesting with an adjusted gestational age to see the ratios again. Not so with Tri-18 and SLOS.

Also, because all 4 of my hormone levels had been low, and because only 2 of them are supposed to increase in levels as pregnancy goes on, retesting with an adjusted age would only fix a couple of the levels, not all...meaning that there might be something else wrong.

It turns out though that if we were at least 7 days off in her gestational age, meaning that she is 7 days younger than we think, then the test was completely invalid. I know when my last period started, but I also have irregular cycles. So it was possible that we were just wrong about her age.

All this left us with a choice to make. Either we are happy not knowing, come back later for another ultrasound and hope that all is well at that time, or do the amnio. Waiting just the 3 days for this appointment had been hell. So I knew I couldn't just not find out. Waiting for another ultrasound didn't guarantee any answers at all, and even then we might end up doing an amnio. Which then we'd end up waiting even longer. So we decided to go through with the amnio, which is scary in itself. It helped that the rate of amnio related miscarriages was really pretty low at this facility, somewhere in the 1 in 500 range. And we took some comfort in knowing that if nothing happened in the 2 weeks after the amnio, that we were out of the woods with most of the worry from amnio related problems (most of the concern is about the hole sealing up).

A lot of people ask me if the amnio was painful. Honestly, I wasn't worried about myself at this point; so I hadn't considered the pain. So when they told me that it's less painful than most people expect and that you just feel some pressure for a minute, I took that to mean it wouldn't be bad at all. And then it was worse than I expected. But still not bad really. Quite uncomfortable for a short period of time, like a minute or so. In my opinion, the pain is definitely not a reason to back out of an amnio. I couldn't even find the place they'd poked when I got home from it, and it stopped hurting almost immediately when they were finished with it.

The waiting at this point was sheer hell. I'm not even going to go into all the thoughts that were in my head during this time.

Because our amnio had been done late Friday afternooon, we'd missed the lab pickup for the day, and the lab didn't get the sample till Monday. Then they had a hard time finding enough cells to test in my sample; so I didn't get the FISH results until Wednesday the next week. Much more agonizing research happened in between these days, and I found a couple sites that are really good for families of Tri-18 babies, but not so good for those of us in my position. Reading about all the babies that were born dead or died so quickly was soooo hard, and yet I kept doing it. It was hard to press through the day, and when I got home from work I'd struggle to stop crying. More than once we called friends and said we had to go out just for the distraction...that I couldn't stop crying unless other people were around.

I called the genetic counselor about a billion times asking if she'd gotten results. She was really sweet, but I felt bad for calling so often. I knew she'd call when she knew, but I still couldn't stop myself. Especially when Tuesday rolled around and still no results at the end of the day. I knew best case scenario we would have gotten them on Monday (the lab can get samples on Saturday...so 3 days from that is Monday). End of day Tuesday was supposed to be worst case...so waiting till end of day Wednesday was hard.

I have a friend at the lab which ran my tests. She could have gotten in a lot of trouble for giving me my results. But guess who still harassed her? She told me info like, "they're starting to test your sample today". But she couldn't tell me much more than that. And I understood that. And I knew that if something were wrong I wouldn't want to hear it from her because that would suck a lot. But I still called. I was still desperate for anything she could tell me.

But the first round of results finally came back, and they showed no mutations. And they showed that our baby is for sure a girl.

We were still worried after this, but the first round of results really gave us such a feeling of relief that it helped us get through the next so long. And we got the next round of results Friday, and they were normal too. So we knew for sure that the baby didn't have SLOS, and we really just had to be worried about the Tri-18 that doesn't show up in all the cells. This made waiting even easier, but still pretty tough. (The kind of Tri-18 that doesn't show up in all the cells can be less devastating than the kind that is in all the cells in some cases...so that was helpful knowledge at this point as well.) Then we got the next round of results earlier the next week than we expected, and they were normal as well!

So the scary quad screen terrified us unnecessarily. Everything it showed as a possibility the amnio ruled out.

The one thing I regret is that we told my in-laws right after we'd had the amnio. We like to keep them informed, and I think we just wanted to talk to people about it as well. When Jason called his mom she was at home by herself. She asked a bunch of questions, and seemed ok. He called her back a few minutes later though to tell her that the US made it look like we were having a girl...and she was apparently quite shaken, and had been sitting at home by herself crying. We didn't want the world to know about all this at this point; so we'd asked her to keep it to herself...which I think made it even worse. At that point we realized that we were done telling family until we had more info. No reason for everybody to be sick with worry.

We've still been worried about the baby's size, but we're more and more convinced that she's just younger than originally thought. Besides that, she looks anatomically good.

So yeah, really the reason I wrote this post, and why I put in so many details that most the world really won't care about is in case there's another terrified expecting parent out there who's going through this. If you are that person, and you need to talk, leave a comment with your email address (leave it on whatever post is newest). Hopefully I'll see it in time to be helpful...

Oh, and some of the details here might be wrong. My memory is a little fuzzy, and Jason remembers some of the details a little differently. Most of the stuff came straight from the notes I took at the time though...so hopefully it's right :) Regardless, this is just the story of what happened to me and what I learned and shouldn't be taken as medical fact.

(One more thing, the quad screen isn't diagnostic...so saying false positive is misleading... I know this, but I Googled for phrases like that when I was desperate and didn't understand this...so maybe it will help somebody find this post who needs to hear a story about a baby whose tests ended up being ok in the end.)