Reading to your baby before the child’s birth can leave a lasting impression. As a baby grows inside a mother’s belly, it can hear sounds from the outside world—and can understand them well enough to retain memories of them after birth, according to new research. It may seem implausible that fetuses can listen to speech within the womb, but the sound-processing parts of their brain become active in the last two trimesters of pregnancy, and sound carries fairly well through the mother’s abdomen. ‘Prenatal babies can hear the rhythm of speech, rhythm of music, and so on,’ says cognitive neuroscientist Eino Partanen of the University of Helsinki.