Objective: To clarify the developmental activity of the autonomic nervous system (ANS) of the normal fetus and intrauterine growth restriction (IUGR) cases using fetal magnetocardiography (FMCG).
Subjects and methods: Normal pregnancy (n = 35) and IUGR (n = 12) cases at 28-39 and 32-37 weeks of gestation, respectively, were included in this study. The R-R interval variability was used to calculate the coefficient of variance (CV(RR)) and low frequency/high frequency (LF/HF) ratio.
Results: The value of CV(RR) in the normal pregnancy group displayed a slight increasing trend with gestational age. However, no such trend was observed in the IUGR group. In contrast, the LF/HF ratio in both the normal pregnancy group and the IUGR group clearly increased over the gestational period; the normal group showing statistical significance.
Conclusion: The development of fetal ANS activity in IUGR cases might differ from that observed in the normal pregnancy group, and this may facilitate early detection of IUGR.