The prenatal ultrasound has become part of routine care for pregnant women, so ubiquitous that doctors rarely explain its risks. Expecting parents happily share these first “pictures” of their babies. With October designated as “Medical Ultrasound Awareness Month” by the joint effort of the American Institute of Ultrasound in Medicine (AIUM) and several other organizations, it’s time to revisit this technology. A prenatal ultrasound, also called a sonogram, uses high-frequency sound waves to create an image of the developing fetus and the mother’s reproductive organs. In allopathic (western, medical) prenatal care, ultrasounds monitor fetal development and screen for any potential problems. The average number of ultrasounds may vary, depending on the doctor or midwife’s concerns for each pregnancy.
How Do Ultrasounds Work?Ultrasounds work by emitting high-frequency sound waves, higher than humans can hear, beginning at 20,000 hertz. A handheld device, called a transducer, sends and receives the ultrasound waves. The sound waves bounce off the structures in the body and produce echoes received by the transducer. The ultrasound machine processes the time it took for the echoes to return and calculates the distance traveled. All of these signals are calculated to form a “picture.” The most familiar ultrasound is the traditional machine with a monitor. However, there are several devices that use ultrasound technology for prenatal care, including:
- Transvaginal ultrasound – A small ultrasound probe that’s inserted into the vagina used in the earlier stages of pregnancy to get a clearer picture.
- 3-D ultrasound – An in-depth ultrasound that displays the width, height, and depth of the fetus and mom’s organs, for diagnosing any suspected problems.
- 4-D ultrasound – A moving video of the fetus. It creates a clearer image of the baby’s face and movements for an even more detailed look at any potential problems. However, the main benefit of 4-D ultrasounds is the keepsake video.
- Fetal echocardiography – An ultrasound that captures an in-depth image of the fetus’ heart, for diagnosing suspected congenital heart defects.
- Doppler – A handheld device for listening to the fetus’s heartbeat at checkups and during labor to confirm it’s in the normal range. Although a picture isn’t formed with the handheld Doppler, it also emits ultrasound frequencies.
- Electronic fetal monitoring belt – An ultrasound device strapped to the mother during labor to continuously record the fetal heartbeat and contractions.
The Many Uses Of Prenatal UltrasoundsUnder standard allopathic prenatal care, ultrasounds are given for many reasons depending on each pregnancy. Generally, ultrasound devices are used to:
- Confirm a viable pregnancy (that the fetus is living)
- Check the fetal heartbeat
- Estimate a due date
- Check for more than one fetus
- Examine the mother’s reproductive organs
- Check for an ectopic pregnancy (when the embryo attaches outside the uterus) or miscarriage
- Monitor fetal growth and position
- Determine the baby’s sex
- Check for placenta previa (when the placenta covers the cervix) and placental abruption (when the placenta detaches from the uterus)
- Check for signs of Down syndrome
- Look for congenital disabilities
- Check for structural abnormalities or blood flow problems
- Monitor amniotic fluid levels
- Check fetal oxygen flow
- Scan for possible issues with the reproductive organs
- Measure cervix length Guide tests such as amniocentesis, where a needle is inserted into the womb to collect amniotic fluid
- Confirm fetal demise
The Known Risks Of Prenatal Ultrasounds On Fetal HealthAsk your doctor if prenatal ultrasounds have risks, and you might hear, “The data’s clear; they’re unquestionably safe.” Yet, an abundance of scientific literature clearly shows that ultrasounds present enough risks to a developing fetus to question the current standard of practice. Some of the health risks of prenatal exposure to ultrasounds that current science shows are:
- Slowed fetal growth
- Increase in delayed speech
- Doppler scans doubling the risk of perinatal death
- Increased risk of autism, ADHD (Attention Deficit Hyperactivity Disorder), DNA damage, jaundice, cancers, and allergies demonstrated in over 50 studies from China
- Increased risk of delivering via c-section based solely on fetal size, as assessed by an ultrasound test and based on continuous fetal heart rate monitoring during labor
Do We Know Enough About Prenatal Ultrasound Risks?The FDA states, “Ultrasounds can heat tissues and in some cases, produce very small bubbles or cavitation in some tissues.” They issued a warning that ultrasounds should be reserved only for medical needs. Additionally, the Doppler for hearing the fetal heartbeat proves to be no better. The handheld Doppler device has been shown to heat tissue higher than safe levels. Another problem is that current-day ultrasound intensity and fetal exposure have yet to be adequately studied. Douglas L. Miller, Ph.D., in his report entitled Safety Assurance in Obstetrical Ultrasound, states:
The present use of diagnostic ultrasound in obstetrics is expected to be essentially free of risk of ultrasound-induced bioeffects. However, it is not possible to prove this expectation […] Scientifically, only the opposite can be shown; that is, continuing research could elucidate a significant harmful effect.”And finally, the American Congress of Obstetricians and Gynecologists states: “No links have been found between ultrasound and birth defects, childhood cancer, or developmental problems later in life. However, it is possible that effects could be identified in the future. ” Does any of the above medical literature alleviate any public concerns about ultrasound safety? Quite the opposite. So, now that the risks are disclosed, the question remains, how necessary are prenatal ultrasounds?