Health Editor’s Note: Some parents choose to withhold vaccinations from their child because they think that these vaccines, which prevent diseases that will maim or kill a child, cause autism. Now, it looks like there is another issue that can be blamed for autism, and ultrasounds have primary access to a developing embryo/fetus months before any possible exposure to a vaccine.
So, are we to believe that the road to autism begins with that first ultrasound? Just what is a fetal ultrasound and why are they done? Ultrasound bombards the embryo/fetus with high-frequency sound waves, that, yes, bounce off of the “little person to be” to produce the image of the baby as it lays in the uterus. Fetal ultrasounds may be performed during the first three months (first trimester) of pregnancy to evaluate whether you are pregnant, how many babies there are, the size of the baby, when the pregnancy began, the evaluation of the placenta and how much amniotic fluid surrounds the fetus,and the location of the baby (inside the uterus) as opposed to in the Fallopian tube (ectopic which will result in surgery for removal of the embryo because a fetus cannot develop in this structure). At this time an ultrasound will also be used to check for fetal abnormalities, genetic or otherwise.
Then in the second and third trimesters additional ultrasounds will be performed to check the anatomy of the baby, to determine if fetal growth is on schedule, to investigate complications such as bleeding,guide needle for removal of amniotic fluid and fetal cells for amniocentesis or chorionic villus sampling, and then finally to determine if the baby is in the desired headfirst position for delivery.
What the information presented here tends to do is to dispel rumors of fetal ultrasounds causing autism. The greatest defense against the “blame vaccines and fetal ultrasounds causing autism: is that according to supportable, medical studies, there are several dozen genes that are responsible for autism [autism spectrum disorder (ASD)]. Remember that a person receives his or her genes from his mother and father. Genes are the beginning of an individual and control whatever that individual will physically become.
The scientific support for genetic contribution to ASD has been achieved with twin studies (both identical and fraternal), family studies comparing first degree relatives who are affected by ASD versus the general population, and studies of rare genetic syndromes that go along with ASD. There may also then be an issue of shared environment as opposed to twins who are raised in parallel lives causing greater or lesser autism changes. What IS common to all ASD is the genetic component that may or may not be exacerbated by environment or issues that come up later in the child’s life.
There is/has been medial research being performed to find the actual cause/causes of autism. Autism begins with genetic make-up and not with vaccines or fetal ultrasounds just as Alzheimer’s disease does not come from getting old. There is a medical reason why some people develop Alzheimer disease and others do not. What we all have in common is that we are all getting older but we all do not share the same genes that affect how that will happen. This is the same for autism. Vaccines and fetal ultrasounds do not cause autism and are relied upon to insure the best chance at healthy fetuses who are then kept safe from life-threatening diseases after they are born……Carol
Is Ultrasound During Pregnancy Linked to Autism?
Study actually reveals ultrasound to be safe, says F. Perry Wilson, MD
by F. Perry Wilson MD, MSCE
A study appearing in JAMA Pediatrics is being reported as showing a link between ultrasound during pregnancy and autism spectrum disorder. But in this Deep Dive analysis, F. Perry Wilson, MD, suggests that the study actually reveals ultrasound to be a safe procedure in this regard. What’s more, the senior author agrees.
The rate of autism spectrum disorder has risen dramatically over the past several decades.
twin studieCenters for Disease Control and PreventionNow, much of that rise has been attributed to an increased recognition and diagnosis of the syndrome, but most experts believe some environmental factor is contributing. While we don’t have a great idea of what that factor is, we’re getting more confident in what it isn’t. First, it isn’t vaccines, either the content or the schedule. I eagerly await your angry emails.
Second, after reading this article in JAMA Pediatrics, I’m fairly certain it’s not prenatal ultrasound.
But I very much doubt that’s the story you’re going to hear with regards to this study. On the contrary, I think you’re going to hear a lot of outlets saying something like “New study links ultrasound during pregnancy with autism”.
First things first – why was this question even studied? Aren’t we always telling our patients that ultrasounds are super safe? Well, ultrasonic energy is energy, and while it may not do much damage as it passes into say, your gallbladder, it may do quite a bit more harm to a developing fetal brain. Some animal studies, in fact, have demonstrated that ultrasonic energy can alter neuronal migration, and at least one study showed that mice exposed to ultrasound in utero had poorer socialization than mice not so exposed.
In other words, there is biological plausibility here. But prior studies looking at ultrasound exposure in pregnancy, including one randomized trial, showed no link with autism.
But these studies were blunt tools – looking at ultrasound as a binary, yes/no type of exposure. Did you get one or not?
The study in JAMA Pediatrics, in contrast, is much more precise. The researchers took 107 kids with autism spectrum disorder and matched them to 104 kids with other developmental anomalies and 209 kids with typical development. They then went back and tallied up all their ultrasounds in utero, but not just the number. They looked at the duration of ultrasound, the frame rate, whether Doppler was used, and also the thermal and mechanical indices – metrics that quantify exactly how much energy is delivered to the imaged tissues.
In total, 9 different ultrasound metrics were assessed. The effect was assessed over the entire pregnancy and in trimester 1, 2, and 3.
Now assessing this much detail is a double-edged sword. If you count it up, we have more than 30 statistical tests here. Some of these were bound to turn up as statistically significant by chance alone as there was no correction done for multiple comparisons.
And that’s just what happened.
Depth of ultrasound was found to be associated with ASD, but none of the other metrics were. Well, duration of ultrasound was associated with ASD in the first two trimesters, but in the opposite direction of what would be hypothesized, with longer duration of ultrasound being protective.
Should we conclude, then, that we should be careful how deep we set our ultrasound scanners? Almost certainly not. There is a very good chance this is a false positive. Even if it’s not, depth of ultrasound is largely determined by anatomy, and maternal body habitus. The observed link may be explained by maternal adiposity.
But more impressive than this is the lack of association with thermal or mechanical index – the biological factors previously hypothesized to mediate any adverse ultrasound effects. If ultrasound is causative in ASD, you would really think that more ultrasonic energy delivered would be worse. This study essentially rules out that possibility, and to me, rules out the possibility that increased ultrasonography in pregnancy is driving the autism epidemic.
But if you don’t take my word for it, ask senior author Dr. Jodi Abbott, whom I spoke with last week about the study results:
“Given the information investigated very very thoroughly, none of the parameters previously associated with harm were found to be different in these populations.”
In other words – the search goes on. But if excellent researchers like Dr. Abbott and her colleague Dr. Paul Rosman continue their in-depth analyses, the search will lead to answers.
- Perry Wilson, MD, MSCE, is an assistant professor of medicine at the Yale School of Medicine. He is a MedPage Today reviewer, and in addition to his video analyses, he authors a blog, The Methods Man. You can follow @methodsmanmd on Twitter.