Teratogenic effects of triamcinolone on the skeletal and lymphoid systems in nonhuman primates

Corticosteroids are used to treat several human diseases, especially allergies, and inflammatory, dermatologic and salt imbalance conditions. Because of the possibility that treatment for one of these conditions might occur before a mother knows she is pregnant and that an effect may be exerted over a period of time which could encompass the organogenic or sensitive period, it is important to establish the teratogenic effect of these drugs. It has been demonstrated that corticosteroids vary considerably in their teratogenic effects. Of the six corticosteroids tested triamcinolone was found to be one of the most teratogenic. The dosage of triamcinolone required to produce a specific defect, cleft palate, was as different between breeds of rabbits as it was between rabbits and mice. The initial objectives of the present study were to compare the teratogenic effects of this drug in three species of nonhuman primates and to develop an animal model for the study of orocraniofacial defects. Observations in the initial experiments indicated that the thymus was affected at a high frequency in the rhesus and bonnet monkeys; consequently, the experiments were extended to include thymus differentiation during later stages of pregnancy and to determine whether the effects of triamcinolone on the fetus result in permanent teratological effects on the lymphoid system.