This is a common refrain from parents who claim that their child’s gender simply miraculously sprung forth with no influence by them. The truth is people aren’t very good judges about how they interact with their children, and any person with a sibling can easily outline the ways in which parents connect with their children in different ways. I would be the last person to argue that biological differences that emerge in reciprocal processes with the in utero environment have no impact on early differences across sex in young infants, but we must also acknowledge that whatever small differences exist are also operated on by a highly gendered social system. This system, in which we operate, contributes to us developing perceptions and expectations about gender and without those cues we may find it difficult to even know how to interact with a child. Just think of times you’ve chatted with someone with a baby in a carriage when you weren’t sure of the sex and how you were careful about the language you used.

Beginning with the study of “Baby X” in 1975, an extensive literature has emerged focusing on the effects of gender labels on the response of adults to infants. The scientists brought in adults to a lab and observed them interacting with a baby presented to the participants as either a girl, a boy, or in neutral clothing with no gender labels used. The elegant part of this study was that the same baby was used across the entire study and adults were just given false information about the baby. Both male and female adults were more likely to select gender-stereotyped toys for the infant if introduced as a girl. In the condition when no gender label was given, all adult subjects made efforts to guess the gender of the child, which were influenced by stereotypical behavior. For instance, if the non-labeled infant exhibited a show of strength the adults would guess that the infant was a boy and adjust their behavior accordingly. Some adults were so awkward and uncertain in the interactions with the baby when no gender info was given that they actually undid the onesie and peaked to see what gender the child was before they could return to a more engaged pattern of play.

In this brilliant manipulation design - since the same baby was used throughout - differential adult behavioral responses to the infants on the basis of gender label can be seen as arising from attitudes and beliefs rather than existing infant gender differences. An interesting replication study - Baby x revisited - went a step further and looked not only at adult behavior in the experiment, but also the behavior of the infant. This is where it gets interesting! Since it was the same baby for all adults, the researchers could see how this gender stereotype behavior by the adults would alter child behavior. And they found that there was in fact a reciprocal transaction such that adults who thought they were handling either a boy or a girl and using stereotypical behaviors in toy selection, level of voice, complexity of language, and sensitivity of handling, did in fact elicit differential behavior from the infant. These infant behaviors, which in general responded positively to either type of treatment, served to affirm and reward the adult’s gendered behavior leading to an amplification of the behaviors and this cycle of contingency. Self-fulfilling prophecies in action!