title: Autologous oocyte cryopreservation in women aged 40 and older using minimal stimulation IVF.
abstract: BACKGROUND
  The value of oocyte cryopreservation in older women remains controversial. The aim of this study was to report the oocyte freezing experience in women aged 40 and older at a single fertility center.
  
  
  RESULTS
  One hundred fifty eight women (mean age 43.9 ± 0.2) who underwent minimal ovarian stimulation IVF were enrolled. IVF protocol included the use of clomiphene citrate (50 mg/day) or letrozole (2.5 mg/day) with or without low dose gonadotropins (started at 75 IU/day and increased as needed to 150 IU/day). 584 retrieved oocytes (2.1 ± 0.15 per patient) yielded 532 mature MII oocytes that were frozen. After thawing and fertilization by ICSI, a total of 344 embryos (1.9 ± 0.1 per patient) were formed. A total of 57 relatively good embryos were transferred and yielded three live births (5.3 % per embryo transfer), three spontaneous abortions, and one chemical pregnancy.
  
  
  CONCLUSIONS
  These data are important in counseling older women who desire autologous oocyte freezing.
authors.affiliation: Reproductive Endocrinology and Infertility, New Hope Fertility Center, 4 Columbus Avenue, New York, NY, USA. johnzhang98@gmail.com.
authors.forename: John J
authors.initials: JJ
authors.lastname: Zhang
authors.affiliation: Reproductive Endocrinology and Infertility, New Hope Fertility Center, 4 Columbus Avenue, New York, NY, USA. simon.choo@nhfc.com.
authors.forename: Simon
authors.initials: S
authors.lastname: Choo
authors.affiliation: Reproductive Endocrinology and Infertility, New Hope Fertility Center, 4 Columbus Avenue, New York, NY, USA. ming.yang@nhfc.org.
authors.forename: Mingxue
authors.initials: M
authors.lastname: Yang
mesh_terms: D000328:Adult; D000367:Age Factors; D015925:Cryopreservation / Q000379:methods* / Q000639:trends; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D054315:Oocyte Retrieval / Q000379:methods* / Q000639:trends; D009865:Oocytes / Q000502:physiology*; D011247:Pregnancy; D018873:Pregnancy Rate / Q000639:trends; D012189:Retrospective Studies