- 5 years ago
Just thought I would share some information I came upon that may be helpful to other moms-to-be here on the hive. My apologies in advance for the length of this post.
I just went for my first OB appointment (first-time mom), and one of the components my clinic routinely includes is a transvaginal ultrasound. I have a very “less is more” philosophy about medicine in general, and particularly with respect to pregnancy and childbirth I strongly prefer minimal intervention. I am also a researcher by training, and I have been doing a lot of reading about the evidence bases (or lack thereof) for many of the practices surrounding pregnancy, labor, and delivery. (For those of you who are also doing this, allow me to recommend evidencebasedbirth.com as an enormously helpful resource! It synthesizes peer-reviewed scientific literature about labor and delivery-related topics and issues.)
Now, let me preface this by acknowledging that the internet is sometimes a wild and crazy place, and if you look hard enough you will find a conspiracy theory or a controversy related to just about anything. I’m not trying to be alarmist about ultrasound across the board. I think that in general they are pretty safe, and that the later in pregnancy you do them, the safer they probably are, based on what we know about fetal development. I also think that early ultrasound is a really important and valuable diagnostic tool for women with risk factors and medical indications (such as bleeding, pain, previous fetal loss, etc.)
However, my husband and I weren’t all that wild about having the early ultrasound as a routine measure. (ACOG, the American College of Obstetrics and Gynecologists, actually doesn’t recommend it as routine procedure, only in medically indicated situations). The main reason it’s done, to accurately date the pregnancy, wasn’t important for us because I have very regular cycles, we chart, and we know our date of ovulation, so the 5-7 day margin of error on the ultrasound would have added nothing to the precision of our timeline. As far as establishing viability and detecting abnormalities, we discussed how termination would not be an acceptable option for us anyway, and, if this baby isn’t destined to make it, knowing that I’d be miscarrying before it actually happened wouldn’t be of benefit for us. I can understand how some women would want to know so that they could prepare themselves, but frankly I think it would just give us an earlier and deeper plunge into the inevitable sadness. Still, I wasn’t sure …
What really convinced both of us was something I found just this morning. There is evidence that first trimester ultrasounds may be correlated with an increased incidence of left-handedness, especially in boys. Why is this important enough to convince me not to have the ultrasound?
During the first trimester, all of the baby’s major organs and systems are forming, including, of course, the brain. Part of the process of brain formation is neural migration, where brain structures settle into place. The transvaginal ultrasounds used early in pregnancy give a clearer picture because they are stronger and get a lot closer to the baby, and they may have a greater likelihood of raising tissue temperatures and altering the way proteins develop in fetal cells. If there turns out to be a link between early ultrasound use and increased left-handedness, that means that the ultrasound is having an effect (possibly small, but nonetheless real) on the development of brain structures.
Now, left-handedness by itself is pretty benign. Still, there may be other subtle impacts that we haven’t uncovered yet, and some people are asking important questions about a possible connection to the rise in incidence of autism. It could be that, if a transvaginal ultrasound is performed just at the wrong point in time when brain tissue is being generated, it could be a factor in altering how those cells arrange themselves. We just don’t know about fetal brain development with enough precision to pinpoint that yet. Darling Husband and I decided that, given that in our case there is so little appreciable benefit from an early ultrasound, we DEFINITELY did not want to do one “just because” if it might alter our child’s brain development. As cool as it might be to see his/her image, we are going to wait until the second trimester when systems development is further along.
Please understand clearly that, in posting this, I am NOT claiming that early ultrasound *causes* autism by any means. The first rule of understanding statistical research is that “correlation does not equal causation,” and autism most likely comes from the interaction of any number of complex factors, both genetic and environmental. It also makes a big difference how skilled the technician is, how strong the transducer is, how old it is (they got a lot stronger after the early ’90s), how long the exposure lasts, etc. My husband and I didn’t have any of this information when we talked it over this morning, and so we decided that in the absence of those details, opt-out was the better choice for us.
For those who want more info on what research exists on this topic, here is a summary with a bibliography you can use to find the complete articles. For anybody who has a legit medical issue or who isn’t able to date their conception through charting, etc., I do think those are good and valid reasons to consider ultrasound. Clearly there are many healthy babies out there who have come out of pregnancies with multiple ultrasounds just fine. But I *DO* encourage people to take it with a grain of salt when someone says, “of course it’s safe, the doctor wouldn’t do it if it wasn’t.” That’s what they said back in the day about taking fetal X-rays, and using thalidomide for morning sickness, and using deep twilight anesthesia for birth, and using forceps aggressively … but eventually, over time, the data accumulated to show that in fact those common practices weren’t well understood and actually weren’t all that safe.
I also think it’s important to not just assume that more medical technology is a self-evident good. It can be useful, but it can also be overused. OBs like how ultrasound lets them give patients those emotional “awww” moments – good marketing for them – and, don’t forget, they are expensive machines. Doctors like to justify their purchase by using them, sometimes more widely than they really ought to be. When that happens, the machines aren’t serving the women, the women are serving the machines. (Incidentally, these are also good questions to ask a few months down the road re. continuous electronic fetal monitoring.) Opting out or delaying may be the right option for you, your baby, and your partner.