Background and purpose: Atrazine causes some biological effects including atresia in ovarian folicules. Essense and aqueous extract of Achillea milifolium and vitamin E are important due to prevention of atresia. Therefore, the effects of these substances were evaluated in ovarian tissue.

Materials and Methods: 42 adult female rats were used. 1^st and 2^nd groups were received atrazine at rates 300 mg/kg/day and 150 mg/mg/day respectively. 3^rd and 4^th groups were received atrazine at rates 300 mg/kg/day and 150 mg/mg/day respectively along with 150 mg/kg/day water extract of A. milifolium. 5^th and 6^th groups were received atrazine at rates 300 mg/kg/day and 150 mg/mg/day respectively along with 100 mg/kg/day essence of A. milifolium. 7^th and 8^th groups were received atrazine at rates 300 mg/kg/day and 150 mg/mg/day respectively and on first day 150 mg/kg a single dose of vitamin E. Microscopic sections were prepared from ovaries. Data were statistically analyzed.

Results: Histomorphometric studies revealed that, the severity of changes in untreated groups with essence and aqueous extract of A. milifolium were more than those groups had been treated with these substances. The results showed highly significant differences (p< 0.001) between treated and untreated groups. The most follicular rescue was in groups treated with aqueous extract of A. milifolium.

Conclusion: The essence and aqueous extracts of the A. milifolium and vitamin E is effective in reduction of adverse changes of ovarian follicles following atrazine exposure.