Abstract：It is very necessary to monitor fetus in perinatal period, and fetal electrocardiogram is one
of the most effective means to monitor fetal’s conditions. Fetal ECG can reflect whole picture of fetal
heart activity. The abnormity in the process of fetal growth and development can be discovered through
the waveform analysis. Many fetal ECG signal extraction methods were described in this paper, such
as adaptive filtering, blind source separation, blind signal extraction, independent component analysis,
wavelet analysis, artificial neural network and so on. The principle and ways to improve the effect of
these methods were introduced, the advantages and disadvantages of these methods were analyzed
at the same time. Fetal ECG signal extraction methods were summarized, and the outlook for future
development of this technology were made in the end of this article.
