Anti-androgenic compounds in breast milk and cryptorchidism among Norwegian boys in the HUMIS birth cohort

The prevalence of cryptorchidism has increased over the past decades, yet its origins remain poorly understood. Testis descent is dependent on androgens and likely affected by endocrine disrupting compounds (EDCs), targeting androgen receptor (AR). We investigated association between anti-androgenic activity, not derived from natural hormones, in maternal breast milk impaired testis among boys. performed a case-control study based 199 samples 94 mothers cryptorchid boys 105 random non-cryptorchid participating Norwegian HUMIS (Human Milk Study) cohort. For each participant, apolar, polar fractions were extracted, combined to reconstitute mixture. Anti-androgenic activity was measured all three using human cell-based vitro anti-AR CALUX® assay expressed μg flutamide equivalent, well-known antiandrogen. Results fraction analyses compared with controls multiple logistic regression, controlling for appropriate confounders identified directed acyclic graph. Children's daily exposure EDCs through breastfeeding estimated 78 eq./kg body weigh/day. higher (1.48 ± 1.37 eq./g milk) mainly representing non-persistent chemicals, contrast other fractions. However, extracts decreased when mixtures apolar fraction, indicating synergistic interactions. No significant difference observed according status polar, or mixed showed nearly samples, at levels than advisory threshold. no antiandrogenic either mixture milk.