Wang JG, Douglas NC, Dicken C, Nakhuda GS, Guarnaccia MM, Sauer MV. Cryopreservation of supernumerary high quality embryos predicts favorable outcomes for patients undergoing repeated cycles of in vitro fertilization.
Fertil Steril 2007;
89:368-74. [PMID:
17509594 DOI:
10.1016/j.fertnstert.2007.03.031]
[Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Revised: 02/20/2007] [Accepted: 03/08/2007] [Indexed: 11/15/2022]
Abstract
OBJECTIVE
To determine whether the decline in pregnancy and implantation rates in repeated fresh IVF cycles is associated with the availability of embryo cryopreservation.
DESIGN
Retrospective study.
SETTING
Assisted reproductive unit at an academic institution.
PATIENT(S)
Women <38 years old (1,037), undergoing nondonor fresh or frozen embryo transfer (FET) cycles between January 1, 2000 and December 31, 2005.
INTERVENTION(S)
In fresh cycles, women used either pituitary desensitization or GnRH antagonists in combination with gonadotropin stimulation protocols before oocyte retrieval. In FET cycles, endometrial development was achieved by oral E(2) and vaginal P after pituitary desensitization. Embryo transfer occurred either on day 3 or on day 5.
MAIN OUTCOME MEASURE(S)
Implantation and pregnancy rates (PR).
RESULT(S)
Excluding FET cycles, implantation rates and PRs declined significantly in repeated cycles compared to the initial one. However, women with supernumerary embryos for cryopreservation appeared to produce embryos with higher implantation potential but were excluded from the analysis. When FET cycles were included, there were no significant declines in PRs for at least three repeated cycles.
CONCLUSION(S)
Embryo cryopreservation stratifies women with high quality embryos from those with low quality embryos who require repeat fresh attempts, resulting in an accelerated decline in observed PRs and implantation rates.
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