2D:4D Ratio in children at familial high‐risk for eating disorders: The role of prenatal testosterone exposure

Abstract

ObjectivesMarkers of prenatal hormone exposure have been associated with the development of eating disorder (ED) behaviors. Our aim was to determine whether 2D:4D ratio, a marker for in utero testosterone exposure, is associated with risk for ED in a large population-based cohort: the Avon Longitudinal Study of Parents and Children (ALSPAC).MethodsThis is the first study to investigate prenatal testosterone exposure in children at high-risk for ED, using 2D:4D as a marker. We compared children whose mothers reported a lifetime ED (anorexia, bulimia, or both; N = 446) to children whose mothers did not (n = 5,367).ResultsDaughters of women with lifetime bulimia nervosa (BN) had lower 2D:4D ratio (B: −0.01, 95% CI: −0.02 to −0.002, P = 0.02), indicating higher prenatal testosterone exposure, than daughters of mothers unaffected by ED. No differences were observed in the male children of women with an ED.ConclusionsFindings suggest that children at high-risk for BN may be exposed to higher levels of testosterone in utero. Fetal exposure to androgen excess is thought to be causal in the development of polycystic ovary syndrome (PCOS), a disorder which is highly comorbid with binge eating and BN. Future research should investigate the potential role of testosterone exposure in utero as a risk factor for BN and binge eating. Am. J. Hum. Biol. 26:176–182, 2014. © 2013 Wiley Periodicals, Inc.

Prenatal and perinatal factors in eating disorders: A descriptive review

“…By contrast, some studies have shown opposite effects of prenatal testosterone exposure on eating disorder risk. For example, lower 2D:4D ratios were observed among daughters of women with lifetime BN compared to daughters of unaffected mothers . No significant differences were observed in sons.…”

“…For example, lower 2D:4D ratios were observed among daughters of women with lifetime BN compared to daughters of unaffected mothers. 23 No significant differences were observed in sons. Another study 24 found lower 2D:4D ratios (i.e., higher prenatal testosterone) in women with AN compared to women with BN, with control individuals intermediary.…”

Obstetric and gynecologic problems associated with eating disorders

“…All participants in the study about hirsutism who were diagnosed with an eating disorder were diagnosed with PCOS . Interestingly, daughters of mothers who had lifetime BN had a lower ratio of the second and fourth digits of the hand (2D:4D), which is associated with high levels of fetal testosterone relative to fetal estradiol and indicates the daughters had had higher testosterone exposure . This may indicate androgens as a link between BN, PCOS, menstrual disturbances, and fertility issues.…”

“…80 Interestingly, daughters of mothers who had lifetime BN had a lower ratio of the second and fourth digits of the hand (2D:4D), which is associated with high levels of fetal testosterone relative to fetal estradiol and indicates the daughters had had higher testosterone exposure. 57 This may indicate androgens as a link between BN, PCOS, menstrual disturbances, and fertility issues. There is evidence that testosterone stimulates appetite, high circulating levels of this testosterone in women have been associated with impaired impulse control, irritability and depression, and antiandrogenic treatment reduces bulimic behaviors.…”

Prenatal testosterone of progenitors could be involved in the etiology of both anorexia nervosa and autism spectrum disorders of their offspring

“…In contrast, views on their effects in eating disorders (ED) are mixed. Specifically, it has been suggested that high prenatal T exposure would have neuroprotective effects (Baker et al, ; Culbert et al, ; Klump et al, ), but also that it contributes to the development of EDs, especially anorexia and bulimia nervosa as demonstrated by the 2D:4D ratio (Kothari et al, ; Quinton et al, ). Regarding animal research, it has been suggested that early exposure to high T during development is related to masculinization in food intake and body weight in female rats (Culbert et al, ).…”