Skip to main content

Sex among siblings: A survey on prevalence, variety, and effects


In a survey of 796 undergraduates at six New England colleges and universities, 15% of the females and 10% of the males reported some type of sexual experience involving a sibling. Fondling and touching of the genitals were the most common activities in all age categories. One-fourth of the experiences could be described as exploitative either because force was used or because there was a large age disparity between the partners. Reactions to the experiences were equally divided among those who considered them positive and those who considered them negative. Females were more likely than males to have been exploited and feel badly about it. Few participants of either sex ever told anyone. The research finds evidence that such experience may have long-term effects on sexual development. Females who report sibling sexual experiences, both positive and negative, have substantially higher levels of current sexual activity. Their level of sexual self-esteem may also have been affected, but more selectively. Those with positive sibling experiences after age 9 have more sexual self-esteem. However, experiences with much older siblings taking place before age 9 are associated with generally lower levels of self-esteem and no increase in current sexual activity.

This is a preview of subscription content, access via your institution.


  1. Burgess, A. W., Groth, A. N., Holmstrom, L. L., and Sgroi, S. M. (1978).Sexual Assault of Children and Adolescents Lexington Books, Lexington, Mass.

    Google Scholar 

  2. Constantine, L. (1977). The sexual rights of children. Paper presented to the International Conference on Love and Attraction, Swansea, Wales.

  3. Estep, R., Burt, M. R., and Mulligan, H. J. (1977). Socialization of sexual identity.J. Marriage Family 39: 99–112.

    Google Scholar 

  4. Finkelhor, D. (1979a).Sexually Victimized Children Free Press, New York.

    Google Scholar 

  5. Finkelhor, D. (1979b). What's wrong with sex between adults and children?Am. J. Orthopsychiat. 49: 692–697.

    PubMed  Google Scholar 

  6. Fisher, S. (1973).The Female Orgasm Basic Books, New York.

    Google Scholar 

  7. Flugel, J. C. (1921).Psychoanalytic Study of the Family, London.

  8. Freud, S. (1963).Three Cases Collier Books, New York.

    Google Scholar 

  9. Hunt, M. (1974).Sexual Behavior in the 1970s Playboy Press, Chicago.

    Google Scholar 

  10. Masters, R. E. L. (1963).Patterns of Incest Julian Press, New York.

    Google Scholar 

  11. Nobile, P. (1978). Incest: The last taboo.Penthouse January, p. 117.

    Google Scholar 

  12. Nunnally, J. C. (1967).Psychometric Theory McGraw-Hill, New York.

    Google Scholar 

  13. Readers discuss family sex (1977).Forum, July, pp. 89–94.

  14. Spainer, G. (1973). Sexual socialization and premarital sexual behavior. Doctoral dissertation, Northwestern University.Diss. Abstr. Int., 1979, University Microfilms No. 73-30, 729.

  15. Straus, M. (1979). Indexing and scaling for the social sciences with SPSS. Unpublished manuscript. University of New Hampshire, Durham, N.H.

    Google Scholar 

  16. Straus, M., Gelles, R., and Steinmetz, S. (1980).Behind Closed Doors: Violence in the American Family Doubleday, New York.

    Google Scholar 

  17. Terman, L. M. (1938).Psychological Factors in Marital Happiness McGraw-Hill, New York.

    Google Scholar 

Download references

Author information



Rights and permissions

Reprints and Permissions

About this article

Cite this article

Finkelhor, D. Sex among siblings: A survey on prevalence, variety, and effects. Arch Sex Behav 9, 171–194 (1980).

Download citation

Key words

  • sibling
  • incest
  • sexual abuse
  • sexual development
  • childhood sexuality
  • sexual socialization