BACKGROUND AND OBJECTIVE: Cyclophosphamide is a drug widely used to treat cancer, skin diseases and immune system disorders. Since cyclophosphamide passes placenta during pregnancy and causes disorders in fetus, this study was conducted to assess the protective effects of galbanum essential oil against cyclophosphamide toxicity in rat placenta tissue.

METHODS: In this experimental study, 19 pregnant rats were divided into 3 groups. On the 13^th day of pregnancy, control group (n=7), cyclophosphamide group (n=7) and cyclophosphamide and galbanum group (n=5) received intraperitoneally a dose of normal saline and cyclophosphamide (15 mg/kg), cyclophosphamide (15 mg/kg) and galbanum essential oil (200 mg/kg), respectively. All rats were euthanized on 20^th day of pregnancy. Placentas were separated and fixed in 10% buffered formaldehyde after their morphology and morphometry was studied. Tissue sections were prepared using the routine techniques of tissue sections preparation and their histology and histometry were studied by light microscopy.

FINDINGS: Cyclophosphamide decreased 0.4 g of placental weight compared with control group (0.5 g) and decreased the thickness and length of large and small diameter of placenta from 3.62, 11.2 and 14.15 mm in control group to 2.81, 9.25 and 11.37 mm, respectively (p≤0.05). Histologically, it decreased the thickness of the labyrinth and basal layers to 385.73 and 72.80 µm and decreased the number of giant cells to 2.45 compared with control group (p≤0.05). Co-administration of galbanum essential oil and cyclophosphamide increased the length of large diameter, thickness of the labyrinth and basal layers and number of giant cells to 12.77 mm, 467.64 and 91.1 µm and 7.60, respectively (p≤0.05).

CONCLUSION: Results of the study revealed that galbanum essential oil can protect placenta tissue against toxic effects of cyclophosphamide