OBJECTIVE: To investigate the effect of diclofenac sodium (DS) exposure on the prenatal development of female rat arteries. STUDY DESIGN: Pregnant rats were separated into control, saline-injected, and drug-treated (DS) groups. Starting from the 5th day following mating until the 15th day of pregnancy, saline and DS (1 mg/kg daily) were injected intraperitoneally into the pregnant rats in the saline and DS groups, respectively. No injection was given to the rats in the control group. Of the offspring born to the pregnant rats, females were chosen. At the end of the 4th and 20th weeks, vessel samples were removed and evaluated using stereological techniques. RESULTS: Our results indicated no significant difference between the volume fractions of the tunica media and lumen in the femoral and brachial arteries of the 4-week-old female rats. Moreover, there were no significant differences between the 4- and 20-week-old female rats in terms of the volume fractions of the tunica media and lumen in their aortas and femoral and brachial arteries. However, a significant difference was observed in the condition of the 4-week-old female rats' aortas. CONCLUSION: Prenatal exposure of female rats to DS may inhibit the development of the arterial system.