Development of Fetal Movement between 26 and 36-Weeks' Gestation in Response to Vibro-Acoustic Stimulation.
BACKGROUND
Ultrasound observation of fetal movement has documented general trends in motor development and fetal age when motor response to stimulation is observed. Evaluation of fetal movement quality, in addition to specific motor activity, may improve documentation of motor development and highlight specific motor responses to stimulation.


OBJECTIVE
The aim of this investigation was to assess fetal movement at 26 and 36-weeks gestation during three conditions (baseline, immediate response to vibro-acoustic stimulation (VAS), and post-response).


METHODS
A prospective, longitudinal design was utilized.


METHODS
Twelve normally developing fetuses, eight females and four males, were examined with continuous ultrasound imaging.


METHODS
The fetal neurobehavioral coding system (FENS) was used to evaluate the quality of motor activity during 10-s epochs over the three conditions.


RESULTS
Seventy-five percent of the fetuses at the 26-week assessment and 100% of the fetuses at the 36-week assessment responded with movement immediately following stimulation. Significant differences in head, fetal breathing, general, limb, and mouthing movements were detected between the 26 and 36-week assessments. Movement differences between conditions were detected in head, fetal breathing, limb, and mouthing movements.


CONCLUSIONS
Smoother and more complex movement was observed with fetal maturation. Following VAS stimulation, an immediate increase of large, jerky movements suggests instability in fetal capabilities. Fetal movement quality changes over gestation may reflect sensorimotor synaptogenesis in the central nervous system, while observation of immature movement patterns following VAS stimulation may reflect movement pattern instability.
Department of Physical Therapy, Crean School of Health and Life Sciences, Schmid College of Science and Technology, Chapman University Orange, CA, USA.
Marybeth
M
Grant-Beuttler
Laura M
LM
Glynn
Amy L
AL
Salisbury
Elysia Poggi
EP
Davis
Carol
C
Holliday
Curt A
CA
Sandman