Fertile Friday: Are Ultrasounds Safe?

Welcome to Fertile Friday!! Let’s talk about ultrasounds. Specifically, are ultrasounds safe? Ultrasounds have become a routine part of prenatal care, but are they overused, and is there any evidence that ultrasounds are harmful to developing fetuses?

I remember back to when I was first pregnant with Valentina. We were referred by my gynecologist to a perinatologist for our care – partially because they were friends so he trusted him, and partially because at the ripe of age of 41, I was automatically considered “high risk”. This perinatologist was a great guy and I’m sure an amazing doctor, but I was told there that I’d be having ultrasounds every 3 weeks throughout the entire pregnancy. It just seemed like an awful lot, especially with no history of genetic disorders of any kind in either of our families, and frankly, I think I’m healthier than most 30 year olds. But that was going to be the protocol. After thinking it all through, and discussing it with this doctor, we ended up moving into midwife care which suited us much better. There were still ultrasounds, but not nearly as many – until the end, of course, when the non-stress tests meant ultrasounds twice weekly for the last month.

What could be harmful about ultrasounds?

Ultrasounds emit high frequency sound waves. They may heat the tissues of the baby, and they can cause jarring to the tissues through the vibrations of the waves. Even the FDA said in 2004, “ultrasound is a form of energy, and even at low levels, laboratory studies have shown it can produce physical effect in tissue, such as jarring vibrations and a rise in temperature.”

The rise in fetal temperature seems to be the most potentially harmful issue, and associations have been made between hyperthermia and neurodevelopmental issues such as ADHD, autism; ophthalmic issues; skin problems such as eczema; allergies; and childhood cancers (based on 50 human studies conducted in China).

Could ultrasounds be a piece of the puzzle in autism? Childhood cancers?

One of the problems is that in the Western world, research has been limited as it is considered unethical to conduct human studies. Animal studies have shown that ultrasound does correlate with neurodevelopmental issues.

Here is a quote from an article in Midwifery Today:

Early studies showed that subtle effects of neurological damage linked to ultrasound were implicated by an increased incidence in left-handedness in boys (a marker for brain problems when not hereditary) and speech delays. Then in August 2006, Pasko Rakic, chair of Yale School of Medicine’s Department of Neurobiology, announced the results of a study in which pregnant mice underwent various durations of ultrasound. The brains of the offspring showed damage consistent with that found in the brains of people with autism. The research, funded by the National Institute of Neurological Disorders and Stroke, also implicated ultrasound in neurodevelopmental problems in children, such as dyslexia, epilepsy, mental retardation and schizophrenia, and showed that damage to brain cells increased with longer exposures.

I believe there is a real lack of awareness around this and pregnant women continue to have more and more scans, following their doctors’ advice. They are told there is no risk at all, or that the benefit far outweighs any risk.

I do think, as with many medical interventions such as vaccines, that the increase in number of ultrasounds given is significant. I know when I was pregnant, my family in Australia were shocked at how many ultrasounds we had. My sister had two during her entire pregnancy, I’d had eight by the end of my first trimester. Also, in 1991 the FDA raised the allowed frequency intensity levels by a factor of eight, so the amount of exposure at each session is higher now than it used to be.

I would be interested to talk to more midwives and see how they feel about this. I have to admit, towards the end of my pregnancy, I was feeling that there were so many ultrasounds, and every time I could see the bill adding up as they were not fully covered by insurance. And there were soooooo many mamas in that room getting their ultrasounds and heart rate monitors too. It definitely seemed good for the hospital’s business. I was also told by one of the nurses that the hospital had changed it’s parameters for diagnosing gestational diabetes, which put more women into the “high risk” category which meant getting non-stress tests, and that they’d been “run off their feet” since that change happened.

I’m not saying that all ultrasounds are bad. But perhaps it’s time to re-evaluate how many are being given, and avoiding exposure where possible. Commercial ultrasounds, where one can go and have 3D or 4D pictures done, are probably even more harmful because of the higher acoustic output needed for those high-definition images.

Not even knowing much about it, we knew that ultrasounds every three weeks for the duration of pregnancy was too much for us. When I think back to those days, I remember being so excited to take the pictures home to send on to Granma- first a blob looking thing, then an alien-looking thing, then a teddy bear-looking thing, then finally, a baby-looking thing!! But then it started feeling like too much intervention in a situation where there was no apparent problem at all (other than my age, of course!).

If this is of interest to you, I found two articles that I really liked, one in Midwifery Today and one on the Healthy Home Economists page. I encourage you to do some further reading on this topic.