Roller Coaster Pregnancy

Thanks again to all the people who left congratulations and well-wishes on last week’s ultrasound picture post. The positive thoughts are much appreciated, especially since it’s been a bit of a roller-coaster here in Chateau Steelypips.

As you can guess from the fact that the ultrasound looks fairly baby-ish, we’ve known about this for quite a while– that’s an 18-week ultrasound, and we told our parents about the pregnancy at Christmas. Things took a somewhat unpleasant turn in early January, though– all appears to be well now, but there were a couple of really unpleasant weeks in there.

In early January, Kate had her first appointment with her OB-GYN, and came home with a bag full of free promo fliers, and pregnancy magazines (which we had fun mocking) as well as an appointment for an ultrasound, just to nail down the date of conception. A week later, she went off to her appointment, and I went in to work, because I expected that there wouldn’t be anything to see. She called me at work, all happy and excited, having seen the heart beating on the ultrasound monitor. This was the first point where the whole thing started to seem real, and we were both ecstatic.

An hour or so later, the doctor called back to say there was a problem.

One of the things they do with a first-trimester ultrasound is to measure the thickness of an area at the back of the baby’s head, called the “nuchal translucency.” This is an important early screening test for a wide variety of genetic disorders, including Down syndrome, trisomy 18, and trisomy 13. The nuchal translucency for our baby was significantly thicker than normal, indicating a greatly increased risk for those conditions.

This was, as you might imagine, pretty devastating news. There are some blood tests for further screening, so we went back to the office for those (I went along this time, as moral support), and were referred to a local specialist. The next week, until the first meeting with the “genetic counselor” was pretty unpleasant– both of us were on edge the whole time, and I don’t think I got a full night’s sleep that entire week.

The blood tests more or less ruled out trisomy 18, but the overall screening indicated a 1 in 10 chance of Down syndrome. We scheduled an amniocentesis to find out for sure, and went back a week later for the procedure (I was there for the ultrasound bits, but I have a deep and irrational hatred of needles, so I left the room for that bit). They said it would probably be a few days before the “FISH test” (“fluorescence in situ hybridization”)for chromosomal disorders came back, and up to two weeks for the full screen. We settled in for another uncomfortable wait, but it was less than 24 hours before they called back with the news that the FISH test was all clear. No chromosomal abnormalities were found. The full genetic screen confirmed it a week or so later.

There’s still an increased risk of some heart defects, which was one of the things they checked at last week’s ultrasound, but the doctor there said he didn’t see anything obviously wrong in looking at the heart on the ultrasound (which, by the way, is the coolest thing ever…). We have a fetal echocardiogram scheduled in a few weeks, to find out for sure, but things seem to be OK, so I was given clearance to post that picture.

A lot of people I’ve told this story to have similar anecdotes involving their own kids, or the children of friends, and almost all of them end the same way: “The kid is fine, and I don’t know why they put us through that.”

The thing is, I’m just enough of a scientist that I do know why they put us through that. I’m not happy about those sleepless nights, mind, but I absolutely understand both why they scared us with those results, and why nearly all of those stories end happily.

The figure they gave us for the chance of Down syndrome was one in ten. That’s roughly an eighty-fold increase in the risk for a woman of Kate’s age, which is pretty dramatic. And while Down syndrome isn’t the end of the world– look at Michael Berube for example, who writes beautifully about raising a child with Down syndrome, and still finds time to work for the downfall of Western Civilization– it’s a major, major problem, and something most people would want advance warning of. If the chance of a condition as serious as that is eighty times higher than normal, a doctor has an obligation to tell people.

And yet, nine out of every ten people who get that early screen result will find nothing wrong in the end. The vast majority of the scared prospective parents out there will end up relieved, and wondering why they went through all those sleepless nights. But it’s absolutely the right thing for them to do– we’ve passed laws based on smaller overall risks than one chance in ten of a serious problem.

(Please note that I do not in any way mean to slight that one set of parents who do end up with a child having Down syndrome. I have nothing but admiration for the love and courage of those parents, let alone the people you’ll find via Google who have babies with the other trisomy disorders. I’d like to think I could be that strong a person, if I had to, but I am cravenly relieved that I don’t have to put that to the test.)

So, anyway, all is apparently well at the moment, and we’ve moved back to being more excited than terrified. For now. There are still more tests to be done, and other scary possibilities down the road– nothing gives you an appreciation for the many and myriad ways in which the human body can go wrong than prospective parenthood, and the long list of problems and issues that can crop up. But we’ve gotten through what I fervently hope will be the scariest moment of this whole process, and we’re looking forward to the arrival of FutureBaby.

Comments

  1. #1 Kate Nepveu
    February 25, 2008

    The observant will have noticed that we were not *planning* on doing the first trimester screen, having no reason to think there was any increased risk. Instead, we were going to wait for the second trimester when a combined screen can be done for additional birth defects. That would have taken place around about now, and might not have showed anything, or if it had, would have let us do the definitive diagnostic tests immediately.

    Instead we had six weeks of stress because the nurse at my first prenatal visit didn’t believe my report of far along I was, and because I didn’t connect the ultrasound-for-dating-purposes with the first half of the first trimester screen.

    Moral: even harmless-sounding tests can have unexpected consequences. In retrospect, I wish I had questioned the nurse a lot more closely about the need for the ultrasound.

    ***

    Note on the first trimester screen. Its stated false-positive rate, which is easily found on the web, is 5%.

    Sounds scary, yeah? But what is less easily found–as in, I only found it yesterday–is the fact that of women whose get a positive return for Down on a screening test (I believe this encompasses both those in both first & second trimester), only 2-3% of their fetuses actually have Down Syndrome. Which, to my naive lawyerly non-scientific reading, is actually more like a 97% false positive rate.

    Since the screening tests return probabilities, 1 in X, the idea of a false positive doesn’t make much sense to me anyway, now that I think about it with some emotional distance. The only thing I can think of is that the 5% is actually the rate of falsely detecting particular substances in the blood or mis-measuring the nuchal translucency. If anyone knows more about this, I’m curious.

    Anyway, I doubt I’d have done or even felt anything different if this had been clearer to me at the time. But it’s worth noting for the record.

  2. #2 Abel Pharmboy
    February 25, 2008

    A lot of people I’ve told this story to have similar anecdotes involving their own kids. . .

    Chalk us up as another similar couple who had the same outcome but also recognize why these tests are done. Ours began with the abnormal combo of alpha-fetoprotein, unconjugated estriol, and beta-hCG that gave us a 1 in 37 chance of Down syndrome in a mother of my wife’s then age. The genetic counseling visit was valuable beyond discussing trisomy 21 in also helping us consider other family health issues to look for down the road. My daughter’s FISH image sits in her baby book.

    By the way, even if the 18-week ultrasound didn’t show the sex of the baby, you most certainly now know it based on the FISH, eh?

    Best wishes to you, Kate, and the little one for a smoother roller coaster ride.

  3. #3 Chad Orzel
    February 25, 2008

    By the way, even if the 18-week ultrasound didn’t show the sex of the baby, you most certainly now know it based on the FISH, eh?

    Our doctors do, but we decided we’d rather be surprised, and asked them not to tell us. I suspect they probably think this is silly, and give it pretty good odds that one or another of them will let it slip at some point, but they’ve been good so far.

  4. #4 bsci
    February 25, 2008

    The one aspect that’s not mentioned here is that amniocentisis is not a risk free procedure. If I remember correctly, it has somewhere around a 1/200 chance of causing a miscarriage (possibly slightly less risky than that). Thus a false positive in the NT test which creates the risk of an unncessary amnio. The risk of amnio is balanced by the parents desire to know about a chromosomal issue in advance, but it does put parents in difficult situations.

  5. #5 Chad Orzel
    February 25, 2008

    The one aspect that’s not mentioned here is that amniocentisis is not a risk free procedure. If I remember correctly, it has somewhere around a 1/200 chance of causing a miscarriage (possibly slightly less risky than that).

    The conselor we talked to seemed to suggest that the risk was lower, when you control for overall health. I think the idea would be that amnio is usually done only when there’s some risk factor present, and that many of the miscarriages that happen after amniocentesis are really due to the factors that led them to do the test in the first place, not the test itself.

    She didn’t lay it out in that much detail, though, and we were thinking about other things at the time…

  6. #6 Denise
    February 25, 2008

    First off, congratulations on the impending addition to the family! I’m so glad that your roller-coaster ride seems to have hit a flat spot. When I was pregnant, I opted for some screening tests that weren’t mandatory for much the same reasons as you stated – I wanted to be prepared for possibilities.

    And, like you and Kate, we decided to keep the gender of our babies a surprise until birth. The doctors and everyone else were very good about NOT telling us, even though they knew – even put big stick-it notes on my chart to remind them that we didn’t want to know. However, I predicted the gender correctly for both my pregnancies.

    If Kate hasn’t already come up with an answer to the question “What are you having?” here are a few suggestions:

    “A baby.”
    “I’m pregnant?”
    “I think it’s an alien, because it sure is taking over.”
    “Emmy thinks it’s a puppy, but we’re pretty sure it’s a baby.”

    Or any variation of the above.

    Again, congratulations, and enjoy the rest of the ride!

  7. #7 bsci
    February 25, 2008

    http://www.aurorahealthcare.org/yourhealth/healthgate/getcontent.asp?URLhealthgate=%2214762.html%22
    Miscarriage -the average risk for miscarriage is less than 1 in 200. Early amniocentesis (before 15 weeks) may have a somewhat higher risk: less than 1 in 100.

    Caughey AB, et al. (2006). Chorionic villus sampling compared with amniocentesis and the difference in the rate of pregnancy loss. Obstetrics and Gynecology, 108(3): 612-616.
    Seems to say it’s slightly higher than 1/200 even in their best age group and time for amniocentisis.

    A standard risk factor is being over the age of 35, which includes many healthy people. Obesity is one risk factor, but you might want to ask your counselor why she thinks it’s much lower in your care.

    Just to make the problem clear, NT has a 5% false positive rate. Of the people who have a postive NT 97% are false positives. Almost all postive NT tests result in an amnio with a 0.5% miscarriage rate. This means there 0.05*0.97*0.005 = 0.024% of all pregnancies end in miscarriage due to a false positive NT followed by an amnio.

    My wife had an NT when she was pregnant and I’d have trouble imagining not getting tested.

    (Kate Nepveu, the reason for your skewed numbers question is that more people tested are negative. Let’s say Down’s happens in 1/1000 births. 1,000,000 people get an NT test. 5% i.e. 50,000 have false positive findings. 100 are true positives. Thus, given the total population, with a 5% false positive rate, 98% of the positive findings are false positives.)

  8. #8 Uncle Al
    February 25, 2008

    The historic birth defect decision engine was the midwife. Defective babies were routinely stillborn. We have embraced improved means to deteriorated ends.

    If it isn’t right and can’t be fixed, lose it. Maxillofacial defects are remediated by routine surgery. Spina bifida, trisomy, rubella… cannot be brought up to spec and are sucking financial wounds. Triage. Invest in what you want; do not invest in what you do not want. This is 2(pi) steradians opposed to all aspects of American social policy, thereby being empirically validated.
    depp=true

  9. #9 Johan Larson
    February 25, 2008

    Kate, I disagree with Denise’s advice about revealing the sex of your baby. Leaving it unknown messes up English grammar. The “he” and “she” pronouns, lacking an ungendered equivalent that is fit for folk (as opposed to livestock), in their majesty demand that the sex of your baby be made known.

  10. #10 Kate Nepveu
    February 25, 2008

    Johan, the answer to “Do you know the sex / What sex is it?” is (in our case) “we don’t know.”

    The answer to “What is it?” is “a fetus,” or other suggestions such as Denise’s.

    Chad, IMO comment #8 has too many vowels.

  11. #11 Chad Orzel
    February 25, 2008

    Chad, IMO comment #8 has too many vowels.

    Absolutely. I was at the gym, or I would’ve gotten that sooner.

  12. #12 Mike
    February 25, 2008

    Kate:

    Personally, I’d answer “What are you having?” with something like “A small pepperoni pizza, if you don’t mind.”

    But that may be the fact that my lunch sucked, and it’s a few more hours until dinner…..

    (And for the record, we didn’t know Rebecca’s gender until she was born. Our attitude was “Hey, if you know it means we don’t get baby clothing that’s all white and yellow, but we don’t care,” which was good, since she was rather uncooperative with the ultrasound techs. We didn’t even really get a shot of her face, ever….)

  13. #13 nik
    February 25, 2008

    This is a pretty new test, and my hunch, as a biomedical engineer studying ultrasound, is that they haven’t quite gotten the sensitivity of the test fine tuned. In one of my grad classes, the prof told us that when fetal heart rate monitors were introduced in the early 80s, I guess they didn’t really know the normal range of fetal heart rates. The result was that lots of women ended up getting caesarians because of fetal distress when there was none. They had set the upper limit for heart rates too low. Figured it out eventually. I’ve heard more anecdotes about the nuchal translucency test, too.

  14. #14 CCPhysicist
    February 25, 2008

    That is all great news, and we wish you well.

    In the old days, they just waited to see what came out. That had its positives and negatives. One positive is that the entire bill for my delivery, including a hospital stay, was less than your co-pay.

    But what I really want to know is what you would have done if the doctor had said “The results of our tests indicate you are going to have an Uncle Al, but otherwise everything is fine”?

  15. #15 Umstandsmode
    February 26, 2008

    congratulations from me too.