Are Ultrasounds a Good Idea?
Mar 4
Written By Trista Birdzell
Are you blindly accepting routine ultrasounds ?
When it comes to understanding what is safest for you in pregnancy, we forget to look at ultrasounds. Do they really make things safer for you and baby? I want to dive into the way we view ultrasounds in the modern day and help you decide what would feel best for you.
Most people that are pregnant will get at least one ultrasound with the majority having 2 or more. It has become common and assumed safe because it is a routine part of prenatal care. So we don't even think to question its safety level or if it is truly needed. Believe me, I understand from personal experience the comfort seeing your baby on the ultrasound machine can bring. However, I think it is important that if anything can pose potential risk to your unborn baby you as the parent should be the one to make the decision if that is something that feels right to you. It's my hope that with this article I can give you some things to use in your tool bag when making decisions.
First let's take a brief look into the history of ultrasounds. The first ultrasound was developed during WWII to detect enemy submarines and was used in the steel industry. In 1955 Glasgow surgeon Ian Donald began experimenting on abdominal tumors that were removed from patients. After that commercial machines became available in 1963 and by 1970 they became a routine part of obstetric care 2.
Now let's look at the studies done to check on the level of safety in pregnancy. There are not many recent or many studies in general. And when performed there is no definite answer if ultrasounds improve the outcome of perinatal mortality. Here are the results from Cochrane Database Syst Rev. 2010 Apr 14;(4):CD000182. doi: 10.1002/14651858.CD000182.pub2.
PMID: 20393930 Review. Nine trials were included. The quality of the trials was generally good. Routine ultrasound examination was associated with earlier detection of multiple pregnancies (twins undiagnosed at 26 weeks, odds ratio 0.08, 95% confidence interval 0.04 to 0.16) and reduced rates of induction of labour for post-term pregnancy (odds ratio 0. 61, 95% confidence interval 0.52 to 0.72). There were no differences detected for substantive clinical outcomes such as perinatal mortality (odds ratio 0.86, 95% confidence interval 0.67 to 1.12). Where detection of fetal abnormality was a specific aim of the examination, the number of terminations of pregnancy for fetal anomaly increased.
Next let's cover some of the benefits of getting an ultra sound and the arguments for them. Ultrasounds have the potential to detect anomalies and help to decide on an action step before labor begins, help to identify the placement of the placenta, identify if there are twins and there chorionicity ( seeing if the twins share or have their own placenta. )
Some downsides of ultrasounds. There isn’t a lot of data on ultrasounds tested on humans, most studies done have been on mice. The temperature of the ultrasound can increase the temperature of the baby's tissues and bones. The unborn baby is being exposed to non-ionized radiation which affects the cells of the baby, if an ultrasound is done to check babies weight know that this is highly inaccurate and can be 2lbs off in either direction. If anything this ultrasound can increase your risk for a cessation if the baby is suspected to be larger than your provider is comfortable with. Measuring the amniotic fluid index (AFI) is also not always accurate. It can give us a general idea of how much fluid is in there but depending on the day, time and technician it can vary.
Your decision does not have to be “ do I get an ultrasound or do I not” it can be, how do I feel about getting one at this time of my pregnancy?
My recommendation
before looking to outside sources for information, first get quiet with yourself and your baby.
Do you have the answer you need or are you needing to fill in the gaps that an ultrasound can potentially answer for you?
If you do decide to get an ultrasound you can choose just the one at 20 weeks which is the fetal anatomy scan and can give you the most information.
To limit the radiation exposure to your baby you can do these things, you can ask them to limit the time exposed and to not use the color flow.
You can request that an ultrasound only be done when medically indicated.
Dr. Stu , a home birth obstetrician, said in a recent podcast episode talking about ultrasounds “ if this test won't change the direction of care, then do you need to do it? …… Only order a test if its going to change your management.” and I really liked that comment.
From what I see ultrasounds are convenient for providers. They offer us the illusion of control, helping to ease some anxiety but also has the potential to create more. Such as in the event the ultrasound technician or radiologist sees something abnormal but isn’t sure so you are then sent for a follow up and in the time frame you are worried about the results. They also are covered by insurance companies with most paying for at least 1-2 during your pregnancy. There is no reason a provider wouldn’t want to do a quick scan to make a couple hundred to a thousand dollars. So before you just accept the routine ultrasound scan, check in with yourself and ask if it feels like the best thing at this time? Some argue that ultrasounds diminish the intuition of the mom and some say that it allows them to connect to their baby more. None of us are the same and as a student midwife that values individualized care, what are you needing at this time?
Works Cited
1. Abramowicz, Jacques S. “Benefits and Risks of Ultrasound in Pregnancy.” Seminars in Perinatology, vol. 37, no. 5, 2013, pp. 295–300, www.ncbi.nlm.nih.gov/pubmed/24176149, https://doi.org/10.1053/j.semperi.2013.06.004. This article is a systematic review of the evaluation of the risk of birth defects related to the use of assisted reproductive technology. The article talks about the risk that reproductive technology has to contribute to congenital birth defects by using information from 11 different studies.
2. Buckley, Sarah. “Ultrasound Scans- Cause for Concern.” Dr Sarah Buckley, 4 May 2017, sarahbuckley.com/ultrasound-scans-cause-for-concern/. In this article Dr. Sarah J. Buckley reviews the history of ultrasounds and the potential risks they pose on the developing baby. She references multiple studies about the potential side effects of ultrasonic exposure.
3. Davies, J. A., et al. “Randomized Controlled Trial of Doppler Ultrasound Screening of Placental Perfusion during Pregnancy.” Lancet (London, England), vol. 340, no. 8831, 28 Nov. 1992, pp. 1299–1303, pubmed.ncbi.nlm.nih.gov/1360032/. Accessed 19 Feb. 2023. This article reviews a randomized controlled trial to assess the effect on primary management and outcome of routine doppler ultrasound examinations of the umbilical and uterine arteries during pregnancy. The outcome was that they did not see that ultrasound improved outcomes.
4. Howland, Genevieve. “The Truth about Baby Ultrasound.” Mamanatural.com, 2019, www.mamanatural.com/baby-ultrasound/. In this article Genevieve Howland describes the risks and the benefits of ultrasounds in a non biased way, allowing the reader to take in all of the information to make their own decision when it comes to choosing to do ultrasounds in their pregnancy. Genevieve gives alternative options to the ultrasound for example if someone is doing it just to know the sex of the baby, they can also do so with a blood test. The author cites different studies and articles for the reader to do more reading if needed.
5. L, Brickere, et al. “Routine Ultrasound in Late Pregnancy (after 24 Weeks’ Gestation) to Assess the Effects on the Infant and Maternal Outcomes.” Www.cochrane.org, 29 June 2015, www.cochrane.org/CD001451/PREG_routine-ultrasound-in-late-pregnancy-after-24-weeks-gestation-to-assess-the-effects-on-the-infant-and-maternal-outcomes. Accessed 19 Feb. 2023. This article give a summary of thirteen studies involving 34,980 women who were randomly selected to screening or a control group (no or selective ultrasound, or ultrasound with concealed results) to see the risks and outcomes of ultrasounds.
