Cosmetic surgery in Iran is suggested to be the most common. The aim of this study was to determine the social factors affecting decision on undergoing nasal cosmic surgery.

100 participants were enrolled in this study (50 participants undergone nasal surgery and 50 controls who had no intention to apply for plastic surgery. Controls were selected among friends and relatives of the surgery group and were matched for sex, age (±1year), marital status, income and education (in the same category as surgery group).

A self administered questionnaire was used to measure social and family factors namely: having a car, having a house, father's job, mother's job, the participant birth order, out of marriage sexual contact, and number of sisters. Multivariate logistic was used to analysis the data.

Among the factors used in the final model only number of sisters shown a positive and significant association with application for nasal surgery (P = 0.019).

Being adjusted for monthly income and no significant association with the participant's father's or mother's job (social class of the participants) may explain the high rate of cosmic surgery among Iranian population. While matched for sex, a direct and significant association between number of sisters of the participants and undergoing plastic surgery suggests the importance of family members and their gender in making decision on undergoing nasal cosmic surgery.