Tooth development or odontogenesis is a very complex process involving many growth factors and transcription factors of genes to ensure an ordered and controlled development of tooth germs. Increasing use of herbal remedies by mothers during pregnancy to avoid side effects of medical drugs may cause systemic and local effects on tooth development. In this study 50 pregnant rats were used, G1 control, GII eucalyptol oil vapour, GIII aloe vera. Offsprings were sacrificed at 1stday and 5th day, the specimens were obtained by serial sagittal sections and stained with (H&E) and Mercuric Bromophenol Blue (special stain). Administration of these herbal medicine during pregnancy result in adverse effects on tooth germ development of the offspring, delay tooth formation, change the thickness of the constituent layers of the teeth and disturbance and altered minerlization of enamel and dentin layers.