Gender stereotypes start soon after birth, influencing adults’ perception of babies’ cries, according to a recent study published in BMC Psychology.

The stereotypical belief that sexes differ in their emotional and cognitive abilities has a large effect on various aspects of human psychology and behavior. The consequence of gender stereotyping spreads throughout society, including having an impact upon the behavior of parents. From the moment a child is born, parents influence their baby boys and girls differently, for example by dressing them differently or encouraging engagement in different activities. All of which contributes to the development of gender identity.

Crying is one aspect of parenting that is a vital signal for babies to communicate their distress and their needs to parents. Whether differences in the cries of babies affect caregivers’ gender attributions, and whether this affects their interpretation of the meaning of cries, had not previously been investigated. Importantly, this should not be the case, as before puberty the cries of boys and girls do not vocally differ.

The study, led by David Reby of the University of Sussex, involved 24 3-month-old infants. The researchers recorded their cries and played them back to various groups of volunteers, including their parents. They measured whether variation in the pitch of cries affected adult listeners’ identification of the baby’s sex, their perception of the baby’s femininity and masculinity, and whether these biases interacted with their perception of the level of discomfort expressed by the cry.

Results showed that low-pitched cries are more likely to be attributed to boys and high-pitched cries to girls, despite the absence of differences in pitch between baby boys and girls. Moreover, low-pitched boys are perceived as more masculine and high-pitched girls are perceived as more feminine. Finally, adult men rate relatively low-pitched cries as expressing more discomfort when presented as belonging to boys than to girls.

The findings show that adult listeners’ generalize gender differences heard in adult voices to the perception of baby’s cries, and that this not only influences their attribution of sex and gender-related traits to crying babies, but also to some extent their assessment of the babies’ discomfort. This may restrict the construction of individual gender identity and the latter might even have direct implications for babies’ immediate welfare, as a baby girl’s intense discomfort might be more easily overlooked when compared with a boy’s.