Introduction: The present study was carried out to evaluate the effect of the beta-lactam antibiotic amoxicillin on the fetuses of albino mice from the morphological and skeletal points of view.
Material and methods: Twenty four adult pregnant mice were used in the present study. They were allocated into 3 groups (8 mice each). The first group served as a control and were injected intraperitoneally (i.p.) with the solvent of the drug and the second and third groups were treated with 205  and  820 mg/kg body weight of amoxicillin for 8 days (gestation days 7-14), respectively.
Results: The morphological examination of the fetuses of treated groups showed growth retardation of mice fetuses as represented by the conspicuous decrease in the average body weight and body length in the two treated groups. No external malformations were recorded among fetuses maternally treated with the low dose of the drug. On the other hand, the fetuses maternally treated with the high dose showed mild external morphological malformations.  In addition, the skeleton of the two treated groups exhibited incomplete ossification in most skeletal elements.
Conclusion: The beta-lactam antibiotic amoxicillin had exerted mild morphological malformations and skeletal abnormalities in mice fetuses maternally treated during organogenesis period of gestation.