In the method according to the invention, the heart sound recording signal obtained from the mother's abdominal wall by the passive acoustic sensor (10) is pre filtered, amplified, digitized and digitally filtered through a programmable amplifier and a filter unit (20), stored in an intermediate memory, and autocorrelation is performed through an autocorrelation unit (30) with a predetermined size time window.The signal obtained as the result of autocorrelation is fed to the input of fuzzy expert system (40), where the local maximum value of the signal, the time position of the local maximum value and the change of the time position of the local maximum value are determined by the fuzzy expert system (40), and the determined input parameters or signals applied as the fuzzy expert system are utilized by the decision stored in the knowledge base The fuzzy rule set of policy logic and the data that can be expected in biology classify them into probability groups and evaluate them.在根據本發明的方法中，將通過無源聲傳感器(10)從母親腹壁獲得的心音描記信號通過可編程放大器和濾波器單元(20)進行預濾波、放大、數字化、數字濾波，存儲在中間存儲器中，並且通過自相關單元(30)以預定大小的時間窗執行自相關。將作爲自相關的結果的所獲得的信號饋送到模糊專家系統(40)的輸入端，其中由模糊專家系統(40)確定信號的局部最大值、局部最大值的時間位置和局部最大值的時間位置的變化，並且將確定出的那些應用爲模糊專家系統的輸入參數或信號，利用存儲在知識庫中的決策邏輯的模糊規則集合和在生物學上能預期的數據將它們分類到概率組中，並進行評估。
