Eyelid movements in normal human fetuses.
OBJECTIVE
We undertook this study to investigate the characteristics of blinking activity in healthy human fetuses.


METHODS
Blinking activity was studied sonographically in healthy fetuses between 33 and 42 weeks' menstrual age. Horizontal and coronal sonographic views of the eye were obtained and videotaped. Fetal blinking movements were analyzed by reviewing the videotape in slow motion. Fetal vibroacoustic stimulation was also used when clinically indicated.


RESULTS
We examined a total of 18 healthy fetuses. Fetal blinking was detected in 89% of cases, with a mean frequency of 6.2 movements per 60-minute observation period. Vibroacoustic stimulation was associated with increased fetal blinking in the 6 fetuses in which it was applied (mean, 15.3 movements per 60-minute observation period).


CONCLUSIONS
Blinking is a normal fetal activity. The increased frequency of blinking activity associated with vibroacoustic stimulation may be considered a part of the normal startle reflex.
Petrikovsky
Boris M
BM
Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Nassau University Medical Center, Third Floor, Women's Pavilion, 2201 Hempstead Turnpike, East Meadow, New York 11554, USA.
Kaplan
Gary
G
Holsten
Nancy
N
D000161:Acoustic Stimulation; D001767:Blinking / Q000502:physiology*; D005143:Eyelids / Q000502:physiology; D005260:Female; D005333:Fetus / Q000502:physiology*; D006801:Humans; D011247:Pregnancy; D016216:Ultrasonography, Prenatal; D014743:Videotape Recording