Comparative Teratogenicity of Triamcinolone Acetonide and Dexamethasone in the Rhesus Monkey (Macaca mulatta)

Pregnant rhesus macaques were treated with 0.5 or 2.5 mg/kg triamcinolone acetonide (TAC) or 1.0 or 10.0 mg/kg dexamethasone sodium phosphate (DEX) between 20 and 50 gestational days (GD). Treatment with TAC at 2.5 mg/kg resulted in a fetal loss of ≷ 71%; 3/5 recovered fetuses displayed an encephalocele or meningocele. All other treatment groups displayed minor cranial skeletal abnormalities consistent with glucocorticoid‐mediated teratogenesis. DEX was shown to have a lower teratogenic potential than TAC in this species.