A couple of years ago I remember a lot of discussion on the groups I follow about ultrasound as a cause of autism. A lot of parents were concerned that they might have done something that resulted in their child’s autism diagnosis.
A recent study in the Journal of Autism and Developmental Disorders looked into the possibility.
Antenatal Ultrasound and Risk of Autism Spectrum Disorders
by Grether JK, Li SX, Yoshida CK, Croen LA..
Here is the abstract:
We evaluated antenatal ultrasound (U/S) exposure as a risk factor for autism spectrum disorders (ASD), comparing affected singleton children and control children born 1995-1999 and enrolled in the Kaiser Permanente health care system. Among children with ASD (n = 362) and controls (n = 393), 13% had no antenatal exposure to U/S examinations; case-control differences in number of exposures during the entire gestation or by trimester were small and not statistically significant. In analyses adjusted for covariates, cases were generally similar to controls with regard to the number of U/S scans throughout gestation and during each trimester. This study indicates that antenatal U/S is unlikely to increase the risk of ASD, although studies examining ASD subgroups remain to be conducted.
The study doesn’t rule out ultrasound completely, but perhaps this will be welcome news to those parents who were concerned.
Left Brain Right Brain 
Hi Sullivan –
Very nicely done re: posting some autism science other than epidemiology or vaccine related.
My wife is more well versed in the potential problems associated with ultrasound; I believe she read some rodent based studies regarding neuronal migration following ultrasound.
The difficult part in reading ultrasound studies in particular is guessing at the interplay between the time after conception when the scans are performed, length of time imaging is performed, and power applied during the ultrascan. I’ve been told that most (all?) of the studies that showed problems in animal models used power outputs much, much higher than generally used in humans, but this subject hasn’t bublbled to the top of my reading queue.
Anyways, it is nice that it is at least being looked at critically.
– pD
Ohhhhh I’m glad my mother hasn’t heard this one. She’s been pretty calm, to my surprise, about my adult dx of Asperger’s, but occasionally mentions something random and unrelated as a possible cause. The hospital she worked in while pregnant with me had just gotten ultrasounds at the time, and I was apparently given an unusual number because they could and the techs wanted the extra practice. I bet she’d like this theory, debunked or no.
http://www.cbc.ca/health/story/2009/08/27/radiation-ct.html
How many did these children have??
My youngest in total had 8 Ultrasounds. 3 before we got to Antenatal and 5 in which included the 2, 24 – 48hrs before he was born (Sat) – one non-stress and one emergency cord one to make certain he was still “alive”. They decided at that point to leave him inutero another 36hrs (Sun, near midnight, induced labour, heart rate crash – which is had done the day we went in and unknown how many times over the 5 days we were there, emergency C-section), even though he wasn’t moving anymore.
I blame those ultrasounds b/c 8 is WAY too many, 8 were used as an excuse to continue keeping in even though 3 weeks early is fine, and it is known that high b/p is not good on the children or the Mother, so we ended up at 2 early instead. Toss in some VERY high blood pressure for 5 days. They fried his brain.
Would he have been born with autism… maybe… his bro was but his is very mild… it’s the severity I blame on the hospital. I’m debating on whether or not to ask for an MRI… will it show Autism or brain damage???
Brain damage shows the same as autism – flapping, spinning, delays etc…. Part of me is curious… How many other’s are like mine out there????
Anecdotal, of course, but my non-autistic son is the one who had tons of ultrasounds because he was large and breech and we tried external version. My autistic son had one, short, make-sure-it’s-one-baby-and-heart-is-fine ultrasound. Not that I think ultrasound is definately safe….but it is good that it’s being studied and, in our case anyway, it doesn’t seem to have been a factor.
pD-
“Very nicely done re: posting some autism science other than epidemiology or vaccine related.”
Thanks for the good words. I would note that this is epidemiology related. It isn’t armchair-epidemiology related, though.
I doubt this study will be the end of the ultrasound discussion. But I thought it worth a short post.
I think this whole line of inquiry deserves to be dismissed at face value. Like MMR and thimerosal, ultrasound was introduced well after the first cases of autism were observed, but well before the 1990s “autism epidemic”. Therefore, there is no chronological correlation from which to even argue the possibility of a causal relationship. The more fundamental problem is that the effects of ultrasound are currently an unknown quantity (certainly deserving further inquiry). Suggesting it as a cause of autism (or any other disorder supposedly needing explanation) is no better than speculating in a vacuum of facts.
Hi David Brown –
It seems to me that it is generally accepted that the behaviors we call autism can have many causes, and our environment has changed a lot since the first ‘real’ case of autism, whenever that was. Relegating all environmental analysis towards autism to a timeframe after case zero seems extremely shortsighted to me.
This study from 2006 shows that an extended exposure to ultrasounds resulted in differential neuronal migration in animal studies.
Prenatal exposure to ultrasound waves impacts neuronal migration in mice
Given the number of other studies we have implicating genetic components with hooks into neuronal migration and autism, I think we have different opinions as towards the utility of this type of research. The details are important; when was the ultrasound given, what was the power in use, and for how long are all going to come into play. These details varied widely from fetus to fetus and over time as ultrasounds have increased in popularity and function; I am of the opinion that we gloss over these details at our peril.
– pD
I had not heard of any connection between ultrasound and autism. Before my second pregnancy, the FDA was warning against the new keepsake 3D ultrasounds and indicated there could be a risk of speech delay in boys from ultrasound exposure. I believe they only referenced a single study and cannot recall which one, but I do remember being very surprised that they would issue a warning based on it. At any rate, I still had ultrasounds as medically needed, but following one of them, a doctor-in-training came in and asked if she could practice ultrasound on me and my baby for half an hour. Um. No.