Multivariate Spectral Analysis of Transabdominally Recorded Intrauterine Acoustic Signals (TRIAS) Across Gestation.

This band-level feature confirmed a statistically highly significant decline during the second trimester (β 1 = −0.7007 dB/week, t = −3.4660, p < 0.05, 95% CI: −1.1180 to −0.2835), demonstrating a continuous shift within this mid-frequency range. 3.6.

also in 132,142 other papers