The purpose of this study was to characterize the different features of body movements for females before and after parturition. Body movement signal was measured by a piezoelectric sensor board which was deployed on the abdominal position beneath a mattress during sleep to monitor pressure changes around abdominal area. Body movement epochs were detected by an innovative algorithm based on Hilbert transform. Data were collected from two healthy pregnant females during sleep for 7 weeks before parturition and 6 weeks after parturition. The pressure signal was used to determine the duration and time interval of maternal movements. Characteristics of the detected body movements before and after parturition were investigated through their proportion. The results showed that before and after parturition, the body movement which features as 0~1 min in interval and 0~6 sec in duration has significant difference statistically. It is considered that these differences are highly correlated with the prenatal activities.