| Abstract: | Hormone transfer theory predicts thatopposite-sex twins will be affected in utero by thehormones their twins produce. This study examines theprediction that opposite-sex dizygotic twins should showless stereotyped toy play than same-sex dizygotictwins should show less stereotyped toy play thansame-sex dizygotic twins as a result of exposure toopposite-sex hormones in utero. Participants in thisstudy included 32 male-female dizygotic twin pairs,27 female-female pairs, and 24 male-male pairs. Allranged in age from 7 to 12 years and were primarilyCaucasian and middle class. Differences in the amount of time children played with feminine,masculine, and neutral stereotyped toys during free playwere examined. Results did not support hormone transfertheory. Girls played with feminine toys more than boys and boys played with masculine toys morethan girls, but there were no significant differencesbetween children with opposite- vs. same-sextwins. |
