title: Serum α-klotho concentrations during preimplantation can predict aging or quality of human oocytes and clinical pregnancy rates.
abstract: BACKGROUND
  To discover simple biomarkers to evaluate the aging or quality of human oocytes and clinical pregnancy rates is needed. However, the association among serum α-klotho concentrations during preimplantation, the aging or quality of human oocytes and clinical pregnancy rates has not been investigated.
  
  
  RESULTS
  The serum α-klotho concentrations during preimplantation decreased due to aging (p < 0.001), whereas the maturation rates of human oocytes (p < 0.001) and the fertilization rates (p < 0.001) improved in association with increased serum α-klotho concentrations. Furthermore, multiple logistic regression analysis showed that the clinical pregnancy rates were influenced by serum α-klotho concentrations during preimplantation (p < 0.001), the patient's age (p = 0.003), maturation rates of human oocytes (p < 0.001), fertilization rates (p < 0.001) and the serum 25 (OH) D levels (p < 0.001) regardless of race (p = 0.29) and BMI (p = 0.96).
  
  
  CONCLUSIONS
  The serum α-klotho concentrations during preimplantation would be a simple biomarker in order to predict the aging or quality of human oocytes and clinical pregnancy rates.
authors.affiliation: Reproductive Medicine Institute Japan, Nakano-ku, Chuo, 3-37-12, Tokyo, 164-0011 Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Takemura
authors.affiliation: Reproductive Medicine Institute Japan, Nakano-ku, Chuo, 3-37-12, Tokyo, 164-0011 Japan.
authors.forename: Midori
authors.initials: M
authors.lastname: Okabe
keywords: Aging or quality of human oocytes; Serum 25 (OH) D levels; Serum α-klotho concentrations
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