Fetal magnetoencephalography in intrauterine growth retarded pregnancies.

Abstract

To investigate the fetal brain activity in pre-eclamptic and normal pregnancies. Biomagnetic measurements were performed by means of a superconducting quantum interference device (SQUID) in an electrically shielded room of low magnetic noise. The study population included 28 pre-eclamptic (34-37 weeks' gestation) and 19 normal pregnancies (34-37 weeks' gestation). The pre-eclamptic group consisted of 11 cases with birth weight below the 10th percentile (1969 +/- 129 g) and 17 cases above the 10th percentile (2496 +/- 257 g). Biomagnetic signals (waveforms) recorded from fetal brains were expressed in terms of magnetic power spectral amplitudes. The total corresponding spectral amplitudes in the frequency range 2-7 Hz were high (719 +/- 69 Ft/ radical Hz in neonates <10th percentile and 537 +/- 105 Ft/ radical Hz in neonates >10th percentile) in most (82%) pre-eclamptic pregnancies and low (382 +/- 35 Ft/ radical Hz) in most normal pregnancies (95%). The difference between normal and all pre-eclamptic pregnancies was highly significant (Student's t-test: p < 0.0001). Comparing the two groups of pre-eclampsia we found also a highly significant difference (Student's t-test: p < 0.0001). Biomagnetic measurements of fetal brain activity could be useful in the assessment of fetal central nervous system development.