Document Detail

Cleavage stage versus blastocyst stage embryo transfer in assisted reproductive technology.
MedLine Citation:
PMID:  22786480     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Advances in cell culture media have led to a shift in in vitro fertilization (IVF) practice from early cleavage embryo transfer to blastocyst stage transfer. The rationale for blastocyst culture is to improve both uterine and embryonic synchronicity and enable self selection of viable embryos thus resulting in higher implantation rates.
OBJECTIVES: To determine if blastocyst stage (Day 5 to 6) embryo transfers (ETs) improve live birth rate and other associated outcomes compared with cleavage stage (Day 2 to 3) ETs.
SEARCH METHODS: Cochrane Menstrual Disorders and Subfertility Group Specialised Register of controlled trials, Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), MEDLINE, EMBASE and Bio extracts. The last search date was 21 February 2012.
SELECTION CRITERIA: Trials were included if they were randomised and compared the effectiveness of early cleavage versus blastocyst stage transfers.
DATA COLLECTION AND ANALYSIS: Of the 50 trials that were identified, 23 randomised controlled trials (RCTs) met the inclusion criteria and were reviewed (five new studies were added in this update). The primary outcome was rate of live birth. Secondary outcomes were rates per couple of clinical pregnancy, cumulative clinical pregnancy, multiple pregnancy, high order pregnancy, miscarriage, failure to transfer embryos and cryopreservation. Quality assessment, data extraction and meta-analysis were performed following Cochrane guidelines.
MAIN RESULTS: Twelve RCTs reported live birth rates and there was evidence of a significant difference in live birth rate per couple favouring blastocyst culture (1510 women, Peto OR 1.40, 95% CI 1.13 to 1.74) (Day 2 to 3: 31%; Day 5 to 6: 38.8%, I(2) = 40%). This means that for a typical rate of 31% in clinics that use early cleavage stage cycles, the rate of live births would increase to 32% to 42% if clinics used blastocyst transfer.There was no difference in clinical pregnancy rate between early cleavage and blastocyst transfer in the 23 RCTs (Peto OR 1.14, 95% CI 0.99 to 1.32) (Day 2 to 3: 38.6%; Day 5 to 6: 41.6%) and no difference in miscarriage rate (13 RCTs, Peto OR 1.18, 95% CI 0.86 to 1.60). The four RCTs that reported cumulative pregnancy rates (266 women, Peto OR 1.58, 95% CI 1.11 to 2.25) (Day 2 to 3: 56.8%; Day 5 to 6: 46.3%) significantly favoured early cleavage. Embryo freezing rates (11 RCTs, 1729 women, Peto OR 2.88, 95% CI 2.35 to 3.51) and failure to transfer embryos (16 RCTs, 2459 women, OR 0.35, 95% CI 0.24 to 0.51) (Day 2 to 3: 3.4%; Day 5 to 6: 8.9%) favoured cleavage stage transfer.
AUTHORS' CONCLUSIONS: This review provides evidence that there is a small significant difference in live birth rates in favour of blastocyst transfer (Day 5 to 6) compared to cleavage stage transfer (Day 2 to 3). However, cumulative clinical pregnancy rates from cleavage stage (derived from fresh and thaw cycles) resulted in higher clinical pregnancy rates than from blastocyst cycles. The most likely explanation for this is the higher rates of frozen embryos and lower failure to transfer rates per couple obtained from cleavage stage protocols. Future RCTs should report miscarriage, live birth and cumulative live birth rates to enable ART consumers and service providers to make well informed decisions on the best treatment option available.
Demián Glujovsky; Debbie Blake; Cindy Farquhar; Ariel Bardach
Publication Detail:
Type:  Comparative Study; Journal Article; Meta-Analysis; Research Support, Non-U.S. Gov't; Review     Date:  2012-07-11
Journal Detail:
Title:  The Cochrane database of systematic reviews     Volume:  7     ISSN:  1469-493X     ISO Abbreviation:  Cochrane Database Syst Rev     Publication Date:  2012  
Date Detail:
Created Date:  2012-07-12     Completed Date:  2012-09-21     Revised Date:  2013-06-28    
Medline Journal Info:
Nlm Unique ID:  100909747     Medline TA:  Cochrane Database Syst Rev     Country:  England    
Other Details:
Languages:  eng     Pagination:  CD002118     Citation Subset:  IM    
Reproductive Medicine, CEGYR (Centro de Estudios en Ginecologia y Reproduccion), Buenos Aires, Argentina.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cleavage Stage, Ovum / transplantation*
Embryo Transfer / methods*
Live Birth / epidemiology
Pregnancy Outcome
Pregnancy Rate
Pregnancy, Multiple
Randomized Controlled Trials as Topic
Update Of:
Cochrane Database Syst Rev. 2007;(4):CD002118   [PMID:  17943767 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Biofeedback and/or sphincter exercises for the treatment of faecal incontinence in adults.
Next Document:  Elective versus symptomatic intravenous antibiotic therapy for cystic fibrosis.