Fetal ultrasound is a common test using sound waves to measure progress and detect potential abnormalities of a developing fetus. Until recently, obstetric ultrasound was considered safe, the gold standard in fetal diagnostics. In addition to being a diagnostic tool, many parents are electing commercially marketed 3D/4D ultrasound video keepsakes. The popularity of these video sessions has raised concern in the medical community. Roy Filly, Professor of Radiology at the University of California Medical Center in San Francisco states, "Sonography is rife with virtually untrained practitioners who are treating this imaging tool like an open cash register drawer."
Before exposing your baby to extraneous ultrasound scans, consider recent research challenging the safety of fetal ultrasounds.
Possible Birth Defects
In 2004, the U.S. Food and Drug Administration issued a warning; "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." A rise in fetal temperature can cause birth defects and significant damage to the central nervous system. Researchers have also looked into a possible link between ultrasound screenings and autism.
A study reported in the "American Journal of Obstetric Gynecology" found that women who had ultrasound examinations had a larger number of preterm births compared to women who received manual pelvic examinations during their pregnancies.
A study reported in the "Lancet" suggests that frequent ultrasound scans may result in the growth restriction in the womb. During the study, 1,415 women received ultrasound scans five times during their pregnancy, while 1,419 women were scanned only once. The women who were more intensively scanned gave birth to smaller babies.
In a study conducted on mice at Yale University, researchers discovered that exposure to ultrasound waves on the unborn mice had a negative effect on brain development. The longer the exposure, the greater the damage. A co-author of the study, Dr. Pasko Rakic states, "Ultrasound has been shown to be very beneficial in the medical context...our study warns against its non-medical use."
Unknown Effects of Repeated Exposure
Audible sound travels at 10 to 20 thousand cycles per second. Ultrasound travels from 10 to 20 million cycles per second. In a study conducted in 2001, a small hydrophone was inserted in a woman's uterus. The recorded sound reached 100 decibels, similar to a subway train coming into a station. In addition to sound, vibration and heat affect the fetus during an ultrasound.
The exposure to the fetus depends on the equipment, length of procedure and number of procedures. Long and short-term effects of accelerated sound waves on a developing fetus are unknown. Beverley Beech, a consumer activist in the United Kingdom calls routine fetal ultrasound "the biggest uncontrolled experiment in history."
- "Midwifery Today": Ultrasound: More Harm Than Good?
- "New Scientist": Fetuses Can Hear Ultrasound Examinations
- "Independent": Ultrasound May Harm Foetuses
- NPR: Ultrasound Affects Brains in Mouse Embryos
- FDA Consumer Magazine; FDA Cautions Against Ultrasound "Keepsake" Images; Rados, C.; 2005