How long do the consequences of parental preference last: A study of twins from pregnancy to young adulthood.

We analyzed depressive and psychosomatic symptoms in relation to parental preference in 419 twins at the age of 22 to 30 years. Depressiveness was elicited with Children's Depression Inventory and reported as a total score and three subscales (low self-confidence, anhedonia and sadness) based on factor analysis as reported in a previous epidemiological study conducted in Finland. Items assessing nervous complaints and somatic symptoms were adapted from Finnish studies of juvenile health habits. Twins reported the preference in two directions: experienced parental preference towards either twin, and twin's own preference towards either parent. About half of the twins were from pairs where both twins experienced having been equally close to both parents, while about 30% were from 'equal and mother's' pair, where one twin evaluated having been preferred by the mother and the co-twin evaluated having been equally close to both parents. According to the twins' own preference, about one third of the twin pairs were 'both equal', one third 'both mother's' and one third 'equal and mother's'. Those male twins who were equally close to both parents (experienced parental preference) had least total depressiveness, while females in the intermediate situation had the highest self-confidence and least anhedonia and nervousness. According to twins' own preference, twins who felt equally close to both parents had the least depressiveness and anhedonia. The intermediate position seems to be the best alternative, as these twins had the least symptoms.