Intrauterine testosterone exposure and risk for disordered eating.

Previous research has suggested that prenatal testosterone exposure masculinises disordered eating by comparing opposite- and same-gender twins. The objective of the current study is to replicate this finding using a sample of 439 identical and 213 fraternal females, 461 identical and 344 fraternal males, and 361 males and 371 females from opposite-gender twin pairs. Disordered eating was compared across twin types using the Eating Disorder Inventory-2. Inconsistent with previous findings, a main effect of co-twin gender was not found. Our results raise questions about the validity of prior evidence of the impact of prenatal testosterone exposure on patterns of disordered eating.