RESUMO
STUDY QUESTION: Compared to families with IVF singletons, what are parental depressive, parent-adolescent interaction and adolescent adjustment outcomes in families with 11-17-year-old IVF twins? SUMMARY ANSWER: No differences were detected for any measured outcome between families with 11-17-year-old IVF twins and those with IVF singletons, despite high statistical power. WHAT IS KNOWN ALREADY: When IVF twins are younger than 5-years-old, parents tend to have more mental health difficulties and poorer parent-child interactions relative to IVF singletons. By middle childhood, these differences may no longer exist and available studies with middle childhood-aged IVF twins challenge the expected long-term implications of the early concerns. IVF twins may even have more optimum adjustment than IVF singletons in middle childhood. STUDY DESIGN, SIZE, DURATION: Study of 280, 11-17-year-old IVF children (n = 122 twins and n = 158 singletons) from 195 families at a US reproductive endocrinology clinic. PARTICIPANTS/MATERIALS, SETTING, METHOD: At Wave 1, clinic patients with an IVF child born between 1998 and 2004 were invited to participate in an online survey. In this follow-up study, mothers and fathers provided information on each of their 11-17-year-old IVF adolescents. MAIN RESULTS AND THE ROLE OF CHANCE: There were no differences between 11- and 17-year-old IVF twins and IVF singletons in parent depressive symptoms, parent-adolescent interactions or adolescent adjustment outcomes. LIMITATIONS REASONS FOR CAUTION: Although the family demographics are representative of IVF patients, participants were drawn from one US clinic. WIDER IMPLICATIONS OF THE FINDINGS: Study results provide reassurance that by adolescence IVF twins and their families function as well as IVF singletons and their families. STUDY FUNDING/COMPETING INTERESTS: University of Minnesota (UMN) Agriculture Experiment Station (MN-52-107), UMN Grant-in-Aid of Research, Artistry and Scholarship, UMN College of Education and Human Development Research Development Investment Grant, UMN Women's Philosophic Leadership Circle Award, UMN Eva Miller Endowed Fellowship. The authors have no conflicts of interest to declare.