en Internal Medicine Internal Medicine Original Research Original Research Clomiphene citrate (CC) has an adverse effect on the quality and quantity of cervical mucus (CM). Poor cervical mucus has been reported in 15% of CC-treated women. CC exhibits estrogen agonist and antagonist activities. Antiestrogenic activity affecting the endocervical glands is theorized to cause a decrease in cervical mucus quality and quantity. An experimental study was performed to assess if there is any relation between poor CM and the level of estrogen in those to whom the drug is administered. We used CC on 50 subjects and evaluated CM and measured serum E2 levels simultaneously. We concluded that there is no relation between the level of estrogen and the quality or quantity of CM in these patients. 225 227 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-298-563&slc_lang=en&sid=1 SAElDEH ZIAEI 20031947532846005987 20031947532846005987 Yes From the Imam Hosein University, of Medical Sciences, Tehran, Islamic Republic of Iran.