Prenatal, Late pregnancy: Pattern leaves a trace
Repeated sound patterns presented late in pregnancy can produce a measurable response before birth and recognition after birth.
A change in movement or heart rate during a familiar voice, phrase, or melody—not a timed performance.
Sing one short melody at a comfortable level. Repeat it naturally; the goal is safe familiarity, never volume.
Sources Granier-Deferre et al. (2011)Partanen et al. (2013)NIOSH prenatal-noise guidance