A continuous, non-invasive fetal heart rate measurement is produced using one or more ultrasonic transducer array patches that are adhered or attached to the mother. Each ultrasound transducer array is operated in an autonomous mode by a digital signal processor to obtain data from which fetal heart rate information can be derived. Each ultrasonic transducer array patch comprises a multiplicity of subelements that are switchably reconfigurable to form elements having different shapes, e.g., annular rings. Each subelement comprises a plurality of interconnected cMUT cells that are not switchably disconnectable. The use of cMUT patches will provide the ability to interrogate a three-dimensional space electronically (i.e. without mechanical beam steering) with ultrasound, using a transducer device that is thin and lightweight enough to stick to the patient's skin like an EKG electrode. The ultrasound device can track the fetal heart in three-dimensional space as it moves due to the mother's motion or the motion of the unborn child within the womb.

An ultrasonic medical imaging apparatus provides an ultransonic transducer constructed with polyvinylidene fluoride. Circuitry is included for generating an energizing pulse for the transducer, the pulse having a predetermined period and an instantaneous frequency which is varied from a first frequency to a second frequency during the period. Circuitry is provided for digitizing electrical signals from the transducer which electrical signals represent ultrasonic reflections received by the transducer in response to the energizing pulse, and a signal processor cross-correlates the digitized electrical signals with the energizing pulse.

A method and apparatus for deriving a pulse sequence corresponding to a fetal heart rate (FHR) from a composite ECG signal which includes a signal from a second source, such as from the mother or a twin. A peak detection technique is used to identify apparent QRS complex signal components in the composite ECG signal, which are then compared against a template by calculating a statistical correlation coefficient. If the correlation result exceeds a predetermined threshold, the complex is flagged as a match. The template is an adaptive one, and is initialized by taking the complexes associated with the first n peaks encountered in the composite ECG signal. It is then continuously updated with each QRS complex which provides an exceptional match. After event sorting and output validation, a sequence of pulses is produced which represents the fetal heartbeat and which can be passed to a conventional heart rate monitor for display. The maternal heart rate can be derived and monitored in the same way, a maternal template being created from identified complexes which fail the correlation against the fetal template. The apparatus and method are particularly applicable to a composite ECG signal monitored by way of an intrauterine probe which is non invasive to the fetus.

A maternal-fetal monitoring system for use during all stages of pregnancy, including antepartum and intrapartum stages. The maternal-fetal monitoring system of the subject invention comprises (1) a set of sensors; (2) an amplifying/filtering means; (3) a computing means; and (4) a graphical user interface. Accurate clinical data, which can be extracted and provided to the user in real-time using the system of the invention, include without limitation, maternal electrocardiogram (ECG) signals, maternal uterine activity signals (EHG), maternal heart rate, fetal ECG signals, and fetal heart rate. In a preferred embodiment, the maternal-fetal monitoring system of the invention includes an intelligence means, such as a neural network system, to analyze and interpret clinical data for use in clinical diagnosis antepartum, intrapartum and postpartum, as well as delivery strategy.