Behavioral and cognitive development as well as family functioning of twins conceived by assisted reproduction: findings from a large population study.

OBJECTIVE: To establish the nature and extent of difficulties in parenting and child development in families with twins conceived by assisted reproduction.
DESIGN: Comparisons were carried out between a representative sample of 344 families with 2- to 5-year-old twins conceived by IVF/intracytoplasmic sperm injection (ICSI) and a matched comparison group of 344 families with singletons from IVF/ICSI. One twin was randomly selected for data analysis to avoid the bias associated with nonindependence of measures.
SETTING: A general population sample of IVF/ICSI families. PATIENT(S): Mothers and children. INTERVENTION(S): Mothers completed a questionnaire booklet. MAIN OUTCOME MEASURE(S): Standardized measures of the mother's psychological well-being (parenting stress, depression, and quality of marriage) and standardized measures of the child's psychological development (emotional/behavioral problems and cognitive development). RESULT(S): Mothers of twins showed significantly higher levels of parenting stress and depression than mothers of singletons and were significantly more likely to find parenting difficult and significantly less likely to obtain pleasure from their child. Regarding the children, there was no difference in the level of emotional or behavioral problems between twins and singletons. However, twins showed significantly lower levels of cognitive functioning. CONCLUSION(S): Greater difficulties in parenting and child development were experienced by IVF/ICSI families with twins than by IVF/ICSI families with singletons.