Birthweight Differences in Adolescent Monozygotic Twins Influence Androgens, Psychological Morbidity, and Health-Related Quality of Life
<b><i>Background:</i></b> Adverse prenatal conditions can exert a long-lasting impact in later life. <b><i>Patients and Methods:</i></b> Thirty-eight post-pubertal monozygotic twin pairs (16 female pairs) with divergent birthweight (bw) due to twin-to-twin transfusion syndrome were examined at a median of 15.1 years. Auxological and endocrine parameters were measured. To evaluate effects of intra-twin bw and hormone differences on mental health, adolescents and their parents completed the Strengths and Difficulties Questionnaire (SDQ), identifying psychological problems. Twins answered the questionnaire on health-related quality of life (HrQoL, KIDSCREEN-52). <b><i>Results:</i></b> Parents attributed a higher number of psychological challenges to the formerly smaller twins, for example, total difficulties (8.8 vs. 6.5, <i>p</i> = 0.009). Differences in bw were associated with differences in parental evaluation of problems, for example, peer relationship problems (<i>r</i> = −0.57 and <i>p</i> = 0.0001). In contrast, bw differences did not affect subjects’ self-assessment of psychological factors but on physical well-being (<i>r</i> = 0.42, <i>p</i> = 0.017). The formerly smaller discordant twins showed significantly lower HrQoL regarding psychological well-being (24.9 vs. 26.6, <i>T</i><sub>1,15</sub> = −2.2, and <i>p</i> = 0.043) and moods and emotions (29.8 vs. 32.0, <i>T</i><sub>1,15</sub> = −2.3, <i>p</i> = 0.039). Higher concentrations of androstenedione were linked to greater psychological well-being (<i>r</i> = 0.39 and <i>p</i> = 0.036) in all twin pairs. <b><i>Conclusion:</i></b> Our results show that the prenatal environment leading to bw differences exerts a long-lasting impact on diverging parental evaluation of mental health. Formerly smaller discordant twins showed significantly lower HrQoL regarding psychological well-being and moods and emotions. Higher androstenedione concentrations were linked to greater psychological well-being.