# BIOEFFECTS OF PRENATAL ULTRASOUND EXPOSURE

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA AT DAVIS · 1993 · $138,457

## Abstract

The long-term objectives are (1) to evaluate the safety of diagnostic
ultrasound and pulsed Doppler in an in vivo system similar to the human,
and (2) to observe if changes in animals exposed prenatally to ultrasound
(scan mode) are the same for pulsed Doppler.  Although considered
noninvasive, the safety of prenatal ultrasound exposure still remains
uncertain.  The current trend to recommend its use as a screening device in
all pregnancies further intensifies the importance of these investigations.
The proposed studies incorporate a nonhuman primate (Macaca fascicularis)
as a model for the human and a commercial ultrasound unit (ATL, MK 600).
Periodic measurements of acoustic output including total power, ISPTA,
ISPPA, and peak rarefactional and compressional pressure will be included
in order to adequately evaluate exposure.  In addition, temporal waveforms
at each location will be recorded and stored throughout the field.  Studies
designed to evaluate the teratogenic potential of prenatal exposure in
laboratory rodents have indicated an increase in the rate of malformations
although long insonation times were incorporated.  A significant rise in
intrauterine temperature (i.e. >2.5degreesC) may be expected with lengthy
exposure although an increase of this magnitude would not be expected in a
clinical setting.  It is proposed that a moderate increase in intrauterine
temperature (<1.0degreesC) can occur with commercial diagnostic equipment
which may be capable of impacting on the developing embryo/fetus.  This
temperature rise may result in a greater absorption of heat within the
brain or at the level of the developing bone.  Since the intensity values
for pulsed Doppler are considerably greater than those employed for routine
imaging, the potential impact on the developing conceptus may also be
greater.  The rise in intrauterine temperature after 10, 20, or 30 minutes
of exposure to real-time ultrasound (scan mode) or 5, 10, 15 minutes of
pulsed Doppler will be assessed by placing a thermocouple probe
transabdominally in vivo with measurements taken intracranially or at the
muscle/bone interface (humerus).  In addition, the decrease in white blood
cells (neutrophils, monocytes) observed in preliminary studies will be
pursued.  Animals will be exposed to ultrasound (scan mode) prenatally as
in prior studies (from 1-5 times weekly during gestation for a total of ~40
exposures).  Pre- and postnatal blood samples will be collected for CBC and
a differential, and postnatal bone marrow stem cell assay.  Finally, the
potential effects of pulsed Doppler exposure on the fetus will be evaluated
by monitoring neonatal, infant, and juvenile development and performance.
These experiments will include the analysis of pre- and postnatal white
cell counts and erythrocyte fragility; and postnatal evaluations of simian
Apgar scores, birth morphometries, growth, hematologic parameters, bone
marrow, and neurobehavioral and behavioral testing.

## Key facts

- **NIH application ID:** 2199627
- **Project number:** 5R01HD025528-04
- **Recipient organization:** UNIVERSITY OF CALIFORNIA AT DAVIS
- **SAM.gov UEI:** TX2DAGQPENZ5
- **Principal Investigator:** Alice F Tarantal
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1993
- **Award amount:** $138,457
- **Award type:** 5
- **Project period:** 1990-06-01 → 1995-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/2199627

## Citation

> US National Institutes of Health, RePORTER application 2199627, BIOEFFECTS OF PRENATAL ULTRASOUND EXPOSURE (5R01HD025528-04). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/2199627. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*