Conformity expectations: Differential effects on IVF twins and singletons' parent-child relationships and adjustment

Increased utilization of in vitro fertilization (IVF) to treat infertility has resulted in a growing twin birthrate. Despite early childhood risks, twins have fewer psychosocial problems in middle childhood than singleton children. This study proposes that parents' conformity expectations for children have differential effects on parent- child relationships for twin and singleton children, which indirectly explains twins' more optimum psychosocial adjustment. Parental conformity expectations, parent- child relationship satisfaction, and children's emotional, behavioral, and attention problems were assessed in a sample of 288 6- to 12-year-old IVF-conceived twins and singletons. Overall, parents of twins had higher expectations for child conformity to parent rules than singleton parents. Path models demonstrate that twin status and parental expectations for child conformity interact to influence parent- child relationships, and this interaction indirectly accounted for differences in twins' and singletons' psychosocial adjustment. Findings suggest parenting constructs have differential influences on the association between twin status and parent- child relationships. Parenting research, predominantly conducted with singletons, should be reexamined before applying existing research to twin children and their families.