During the method concerning the examination of the intra-uterine condition f the foetus, the mechanical vibrations induced by the heart of the foetus, together with other vibrations coming from the body of the expectant mother, are sensed by the at least one electro-mechanical transformer placed on the body surface of the expectant mother, the detected vibrations are transformed into electrical signals； the electrical signals so received are led to the signal processing units and processed, during which the electrical signals are pre-amplified by manually adjustable amplification of automatic amplification control； the frequencies including the heart sound of the expectant mother are removed from the amplified electrical signals of the perceived vibrations by active band filtering； the signal level reduction due to band filtering is compensated for by amplification； the filtered signal is subjected to further transformation before processing, so that it is modulated to a carrier frequency in the range of 5.5-6.5 kHz, and led to the signal processing unit that way； in the signal processing unit, first the modulated signal is demodulated, then it is processed.A device suitable for implementing the method comprises the following main components:- an elastic belt that can be fixed on the abdomen of the expectant mother；- at least one electro-acoustic transducer (22) and filtering and signal conditioning grade (22) detecting mechanical vibration placed in the belt, connected to a communication device (21), preferably a smart phone, preferably through wireless, e.g. Bluetooth, connection；Between the electro-acoustic transducer (22) and the communication device (21), a band filter is inserted, that is designed as band filter cutting off sharply the frequencies of under around 20 Hz and above 200 Hz, and 70 Hz and 300 Hz, respectively, including also the heart sound of the expectant mother.The computer program product to be run on the device, e.g. the smart phone, proc
