Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2015 Mar:69:123-31.
doi: 10.1016/j.yhbeh.2015.01.007. Epub 2015 Feb 2.

Academic performance of opposite-sex and same-sex twins in adolescence: A Danish national cohort study

Linda Ahrenfeldt  1 , Inge Petersen  2 , Wendy Johnson  3 , Kaare Christensen  4
Affiliations

Academic performance of opposite-sex and same-sex twins in adolescence: A Danish national cohort study

Linda Ahrenfeldt et al. Horm Behav. 2015 Mar.

Abstract

Testosterone is an important hormone in the sexual differentiation of the brain, contributing to differences in cognitive abilities between males and females. For instance, studies in clinical populations such as females with congenital adrenal hyperplasia (CAH) who are exposed to high levels of androgens in utero support arguments for prenatal testosterone effects on characteristics such as visuospatial cognition and behaviour. The comparison of opposite-sex (OS) and same-sex (SS) twin pairs can be used to help establish the role of prenatal testosterone. However, although some twin studies confirm a masculinizing effect of a male co-twin regarding for instance perception and cognition it remains unclear whether intra-uterine hormone transfer exists in humans. Our aim was to test the potential influences of testosterone on academic performance in OS twins. We compared ninth-grade test scores and teacher ratings of OS (n=1812) and SS (n=4054) twins as well as of twins and singletons (n=13,900) in mathematics, physics/chemistry, Danish, and English. We found that males had significantly higher test scores in mathematics than females (.06-.15 SD), whereas females performed better in Danish (.33-.49 SD), English (.20 SD), and neatness (.45-.64 SD). However, we did not find that OS females performed better in mathematics than SS and singleton females, nor did they perform worse either in Danish or English. Scores for OS and SS males were similar in all topics. In conclusion, this study did not provide evidence for a masculinization of female twins with male co-twins with regard to academic performance in adolescence.

Keywords: Academic performance; Behavior; Mathematics; School engagement; Sex-difference; Testosterone; Twins.

PubMed Disclaimer

Conflict of interest statement

Conflicts of interest

No conflicts of interest.

References

    1. Bacete FJG, Remirez JR. Family and personal correlates of academic achievement. Psychol Rep. 2001;88:533–547. - PubMed
    1. Baker JH, Lichtenstein P, Kendler KS. Intrauterine testosterone exposure and risk for disordered eating. Br J Psychiatry. 2009;194:375–376. - PMC - PubMed
    1. Bartels M, Rietveld MJ, Van Baal GC, Boomsma DI. Heritability of educational achievement in 12-year-olds and the overlap with cognitive ability. Twin Res. 2002;5:544–553. - PubMed
    1. Benetos A, Dalgard C, Labat C, Kark JD, Verhulst S, Christensen K, Kimura M, Horvath K, Kyvik KO, Aviv A. Sex difference in leukocyte telomere length is ablated in opposite-sex co-twins. Int J Epidemiol. 2014;43:1799–1805. - PMC - PubMed
    1. Berenbaum SA, Bryk KL, Beltz AM. Early androgen effects on spatial and mechanical abilities: evidence from congenital adrenal hyperplasia. Behav Neurosci. 2012;126:86–96. - PMC - PubMed

Publication types

LinkOut - more resources