TY - JOUR
T1 - Fetal movement detection
T2 - Comparison of the Toitu actograph with ultrasound from 20 weeks gestation
AU - DiPietro, Janet A.
AU - Costigan, Kathleen A.
AU - Pressman, Eva K.
N1 - Funding Information:
Contract grant sponsor: NIH; Contract grant number: RO1 HD27592. *Corresponding author: Janet DiPietro, Department of Population and Family Health Sciences, 624 N. Brwdwoy, Johns Hopkins University, Baltimore, MD 21 205. E-mail: idipietr@welchlink.welch.ihu.edu Received 3 May 1999; revised 23 June 1999; accepted 29 June 1999
PY - 1999
Y1 - 1999
N2 - Objective: This study evaluates the validity of Doppler-detected fetal movement by a commercially available monitor and investigates whether characteristics of maternal body habitus and the intrauterine environment affect its performance. Methods: Fetal movement was evaluated in normal pregnancies using both ultrasound visualization and a fetal actocardiograph (Toitu MT320; Tofa Medical Inc., Malvern, PA). Data were collected for 32 min on 34 fetuses stratified by gestational age (20-25 weeks; 28-32 weeks; 35-39 weeks). Fetal and maternal characteristics were recorded. Comparisons between ultrasound-detected trunk and limb movements and actograph records were conducted based both on 10-s time intervals and on detection of individual movements. Results: Time-based comparisons indicated agreement between ultrasound and actograph 94.7% of the time; this association rose to 98% when movements of less than 1 s duration were excluded. Individual movements observed on ultrasound were detected by the actograph 91% of the time, and 97% of the time when brief, isolated movements were excluded. The overall kappa value for agreement was 0.88. The actograph was reliable in detecting periods of quiescence as well as activity. These findings did not vary by gestational age. The number of movements detected by the actograph, but not the single-transducer ultrasound, significantly increased over gestation. Maternal age, parity, weight, height, or body mass index were not consistently associated with actograph validity. Characteristics of the uterine environment, including placenta location, fetal presentation, and amniotic fluid volume also did not affect results. Conclusions: The Toitu actograph accurately detects fetal movement and quiescence from as early as 20 weeks gestation and has utility in both clinical and research settings. Actographs are most useful for providing objective and quantifiable measures of fetal activity level, including number and duration of movements, while visualization through ultrasound is necessary for studies of movement quality, source, or mechanics.
AB - Objective: This study evaluates the validity of Doppler-detected fetal movement by a commercially available monitor and investigates whether characteristics of maternal body habitus and the intrauterine environment affect its performance. Methods: Fetal movement was evaluated in normal pregnancies using both ultrasound visualization and a fetal actocardiograph (Toitu MT320; Tofa Medical Inc., Malvern, PA). Data were collected for 32 min on 34 fetuses stratified by gestational age (20-25 weeks; 28-32 weeks; 35-39 weeks). Fetal and maternal characteristics were recorded. Comparisons between ultrasound-detected trunk and limb movements and actograph records were conducted based both on 10-s time intervals and on detection of individual movements. Results: Time-based comparisons indicated agreement between ultrasound and actograph 94.7% of the time; this association rose to 98% when movements of less than 1 s duration were excluded. Individual movements observed on ultrasound were detected by the actograph 91% of the time, and 97% of the time when brief, isolated movements were excluded. The overall kappa value for agreement was 0.88. The actograph was reliable in detecting periods of quiescence as well as activity. These findings did not vary by gestational age. The number of movements detected by the actograph, but not the single-transducer ultrasound, significantly increased over gestation. Maternal age, parity, weight, height, or body mass index were not consistently associated with actograph validity. Characteristics of the uterine environment, including placenta location, fetal presentation, and amniotic fluid volume also did not affect results. Conclusions: The Toitu actograph accurately detects fetal movement and quiescence from as early as 20 weeks gestation and has utility in both clinical and research settings. Actographs are most useful for providing objective and quantifiable measures of fetal activity level, including number and duration of movements, while visualization through ultrasound is necessary for studies of movement quality, source, or mechanics.
KW - Actocardiograph
KW - Fetal heart rate
KW - Fetal monitoring
KW - Fetal movement
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U2 - 10.3109/14767059909020491
DO - 10.3109/14767059909020491
M3 - Review article
C2 - 10582855
AN - SCOPUS:0032732982
VL - 8
SP - 237
EP - 242
JO - Journal of Maternal-Fetal and Neonatal Medicine
JF - Journal of Maternal-Fetal and Neonatal Medicine
SN - 1476-7058
IS - 6
ER -