title: Effects of selenium, calcium and calcium ionophore on human oocytes in vitro maturation in a chemically defined medium.
abstract: BACKGROUND
  In vitro maturation (IVM) of human oocytes is an emerging procedure quickly incorporated into the world of assisted reproductive technologies. As an effective method of in vitro maturation, several studies have reported the critical role of differentions on activating the complex process involved in both gamete maturation and fertilization.
  
  
  OBJECTIVE
  In this study, we supplemented a chemically defined medium with different combinations of selenium, calcium and calcium ionophore concentrations to obtain the best rate of human oocytes maturation, survival, and fertilization.
  
  
  METHODS
  As an experimental study, Three combinations of [selenium (5 μg/ml), calcium (5 μg/ml) and calcium ionophore (1 μg/ml)], [selenium (10 μg/ml), calcium (7 μg/ml) and calcium ionophore (2 μg/ml)] and [selenium (15 μg/ml), calcium (10 μg/ml) and calcium ionophore (5 μg/ml)] added to the chemically defined medium and the morphology of oocytes assessed after 22-24 hours in vitro maturation of the oocytes.
  
  
  RESULTS
  The highest percentage of MII (meiosis II) oocytes (68%), developing beyond the morula (20.1%) and the blastocyst formation (11.1%) observed in oocytes treated with 15µg/ml selenium, 10µg/ml calcium and 5µg/ml calcium ionophore. Moreover, we showed the significant rate of survival in each three combinations after 36, 72 and 96 hours.
  
  
  CONCLUSIONS
  Maturation and activation of oocytes may be triggered by changes in intracellular ion concentrations as second messengers in signal transduction pathways. Here, we received the highest percentage of in vitro maturation and fertilization among three combinations of selenium, calcium and calcium ionophore treatments. Using this combination of ions beside other factors might be useful for the enrichment of the human oocytes IVM medium.
authors.affiliation: Department of Midwifery, Islamic Azad University, Meybod Branch, Meybod, Iran.
authors.forename: Mehri
authors.initials: M
authors.lastname: Makki
authors.affiliation: Department of Assisted Reproduction Technology, Laboratory of Embryology, Novin Fertility and Infertility Center, Mashhad, Iran.
authors.forename: Elham
authors.initials: E
authors.lastname: Saboori
authors.affiliation: Department of Assisted Reproduction Technology, Laboratory of Embryology, Novin Fertility and Infertility Center, Mashhad, Iran. ; Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Sabbaghi
authors.affiliation: Department of Assisted Reproduction Technology, Laboratory of Embryology, Novin Fertility and Infertility Center, Mashhad, Iran.
authors.forename: Raheleh
authors.initials: R
authors.lastname: Aram
authors.affiliation: Department of Chemistry, Islamic Azad University, Meybod Branch, Meybod, Iran.
authors.forename: Mohammad Hasan
authors.initials: MH
authors.lastname: Fallahian
authors.affiliation: Department of Anatomy, Islamic Azad University, Yazd Branch, Yazd, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Peyghambari
authors.affiliation: Department of Assisted Reproduction Technology, Laboratory of Embryology, Novin Fertility and Infertility Center, Mashhad, Iran.
authors.forename: Hessam
authors.initials: H
authors.lastname: Roustaei
authors.affiliation: Department of Basic Sciences, Laboratory of Embryology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran.
authors.forename: Abbas
authors.initials: A
authors.lastname: Ahmadi
keywords: Calcium; Calcium ionophore; Human oocytes; In vitro maturation (IVM); Selenium