Are ICSI adolescents at risk for increased adiposity?

Puberty is a critical period for the development of cardio-metabolic disturbances, including a more central body fat distribution. It is still unclear if IVF and more specifically ICSI, can permanently and detrimentally affect body fat accumulation in the human offspring. Therefore, adiposity and body fat distribution in 14-year-old adolescents born after ICSI were investigated.

Body composition data, including anthropometry (weight, height and BMI), skinfold thicknesses (peripheral: triceps and biceps skinfolds; central: supra-iliacal and subscapular skinfolds; total: sum of the four skinfolds) and circumferences (waist, mid-upper arm) were compared between 217 ICSI singletons (116 boys, 101 girls) and 223 singletons (115 boys, 108 girls) born after spontaneous conception (SC). ICSI teenagers were part of a previously published ICSI cohort followed since birth; SC controls were recruited from schools in the surroundings.

Among all boys, no differences in body composition measurements were found between the ICSI and SC group, taking into account confounding variables. In boys with more advanced pubertal stages, a significantly higher sum of peripheral skinfolds was found in the ICSI group compared with the SC group (difference 3.5 mm, 95% confidence interval 0.3-6.6). In girls, peripheral adiposity assessed by skinfolds and mid-upper arm circumference, and central adiposity assessed by skinfolds and waist circumference as well as total adiposity assessed by BMI, the sum of four skinfold thicknesses and skinfold-derived body fat percentage were significantly higher in the ICSI group compared with the SC group, taking into account confounding variables (all P< 0.05). Neither parental nor early life factors could explain the differences.

We found that pubertal ICSI girls were more prone to central, peripheral and total adiposity compared with their SC counterparts. ICSI adolescents with advanced pubertal stages showed more peripheral adiposity. Continued monitoring of body fat patterns in adolescents born after fertility treatment is mandatory in order to assess their risk for developing obesity and its related adverse health effects in adulthood.