Current research had been conducted to assess the impact of boric acid (boron) on the different tissues of the fetal and maternal bodies of pregnant mice Mus musculus and its influence on the maternal plasma biochemistry, hematology, in addition to the fetal and maternal bodies weight, moreover the weight of a certain motherly tissues included liver, kidney, lung, brain and spleen. The pregnant mice were administered orally with boric acid at the concentrations of 50 and 100 mg/kg during pregnancy. The observations at a concentration of 50 mg / kg demonstrated several histopathological patterns in different mothers and fetal body parts. The lesions were increased at the dose of 100 mg / kg. Moreover, boron caused weight decrease in the maternal body weight, fetuses, and liver, but it caused an increase in weight of the kidney at the concentration 100 mg/ kg. The biochemical assessment of the maternal serum showed a high rise in the level of liver enzymes, blood urea, creatinine, total protein, total bilirubin, glucose, cholesterol, triglycerides, HDL, and LDL at the concentration 100mg mg/kg. Furthermore, there was a meaningful change in the blood hematology at the concentration 100mg/kg. In conclusion, the exposure of pregnant mice to high concentrations of boric acid can alter the structure, the function of maternal and embryos organs by inducing oxidative stress, which in turn resulting in the accumulation of toxins in the blood that cause different effects during the exposure period.