Cyclophosphamide is an anticancer drug, which is used in chemotherapy. It causes alkylation of the DNA molecule. It is absorbed well by gastrointestinal tract and distributed extensively throughout the tissues and liquids of body. It also passes through the blood–brain barrier. It is turned into the active metabolites in liver and eventually excreted through the kidneys [
1]. Cyclophosphamide applies its cytocidal effect through creating links between the double-stranded DNA molecules, breaking DNA and RNA, and inhibiting protein synthesis. It is an alkylating drug and creates reactive molecules that alkynate the nucleophilic group on DNA arm, especially guanine-N7. It creates lateral links between arms, the abnormal coupling of arms, and break in DNA molecule [
2]. Consuming cyclophosphamide often follows anorexia, nausea and vomiting. Its major side effects include reduced blood cells, elevated concentrations of uric acid, decreased gonadal function, causing amenorrhea, azoospermia, and oligospermia [
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2]. Medicinal plants have been used for many years throughout the world for treatment and prevention of certain diseases; however, the effects of some of them have been studied scientifically. Medicinal plants are beneficial therapies both in modern and traditional systems. Allium species such as onion, garlic are consumed as foods, spices, seasonings, and local drugs. Garlic (scientific name:
Allium sativum from Liliaceae family) has considerably gained attentions among new plants, as it is extended throughout the world and it is available [
3]. Compounds of garlic are many various as C, A, B6, B2, B1, alicine, sulfur, ajoine [
3]. Biological responses of garlic including reduced cardiovascular risk factors, cancer, stimulation of immune activities, increased detoxification of foreign compounds (xenobiotic), anti-microbial and anti-viral effect, antioxidant activity, protection of the generated cells in adult male rats, which reflects its antioxidant role, protected sperm and caused final maturation and sperm evolution [
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5]. As the therapeutic and prophylactic effects of garlic on reproduction after consuming cyclophosphamide have not been studied yet, we attempted to study the effect of garlic extract on changes of serum concentration of LH, FSH hormones, testosterone, and spermatogenesis. As the chemical drugs, especially chemotherapy drug of cyclophosphamide decrease spermatogenesis, and reduce reproductive activity, and garlic contains antioxidant compounds, inhibitors of active metabolites, and free radicals, it can be partially predicted that garlic extract compounds reduce the damaging effects of cyclophosphamide on reproduction process [
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