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Updated: Jul 10, 2026
10:59
Human Blastocyst Biopsy and Vitrification
Published on: July 26, 2019
Cleavage stage versus blastocyst stage embryo transfer in assisted conception
D A Blake1, C M Farquhar, N Johnson
1Auckland University of Technology, Biotechnology Research Institute, Private Bag 92006, Auckland, New Zealand, 1020. debbie.blake@aut.ac.nz
The Cochrane Database of Systematic Reviews
|October 19, 2007
Summary
Blastocyst embryo transfer significantly increases live birth rates compared to cleavage stage transfer, especially for good prognosis patients. This advanced technique offers improved outcomes in in vitro fertilization (IVF).
Area of Science:
- Reproductive Medicine
- In Vitro Fertilization (IVF)
- Embryology
Background:
- Advances in cell culture media have shifted IVF practice towards blastocyst stage transfer.
- Blastocyst culture aims to improve uterine-embryonic synchrony and embryo selection for higher implantation rates.
Purpose of the Study:
- To compare live birth rates and associated outcomes of blastocyst stage embryo transfers (ETs) versus cleavage stage ETs.
- To identify factors influencing these outcomes.
Main Methods:
- Systematic review and meta-analysis of 18 randomized controlled trials (RCTs) identified from multiple databases.
- Primary outcome: live birth rate per couple. Secondary outcomes: clinical pregnancy, multiple pregnancy, miscarriage, embryo transfer failure, and cryopreservation rates.
Main Results:
- Blastocyst transfer showed a significantly higher live birth rate (36.0%) compared to cleavage stage transfer (29.4%) (OR 1.35).
- This benefit was most pronounced in good prognosis patients, with similar embryo numbers transferred, and randomization on Day 3.
- Embryo freezing rates were higher in cleavage stage transfers, while transfer failure rates were higher in blastocyst transfers, though not significantly different for good prognosis patients.
Conclusions:
- Evidence supports blastocyst transfer as superior for pregnancy and live birth rates, particularly in good prognosis patients.
- Blastocyst culture may be suitable for single embryo transfer in selected cases, with no difference in cycle cancellation rates for specific subgroups.
Related Concept Videos
01:33Cleavage and Blastulation
After a large-single-celled zygote is produced via fertilization, the process of cleavage occurs while zygotes travel through the uterine tube. Cleavage is a mitotic cell division that does not result in growth. With each round of successive cell division, daughter cells get increasingly smaller.
01:24In Vitro Fertilization
In vitro fertilization (IVF) is a form of assisted reproductive technology where an egg is fertilized with sperm in a controlled laboratory environment before transferring the resulting embryo into the uterus. This process is designed to help individuals and couples experiencing difficulties conceiving.
The IVF process begins with ovarian stimulation, during which reproductive endocrinologists prescribe hormonal medications to stimulate the ovaries to produce multiple eggs instead of the single...
The IVF process begins with ovarian stimulation, during which reproductive endocrinologists prescribe hormonal medications to stimulate the ovaries to produce multiple eggs instead of the single...
01:10Zygotic Development And Stem Cell Formation
The development of all multicellular organisms starts with the fusion of haploid cells called sperm and egg to form a diploid zygote. A zygote is a totipotent cell that can develop into a complete organism. The zygote undergoes cell division or cleavage to form an 8-cell mass. Until this stage, the cells are spherical, loosely attached, and remain totipotent. Totipotent cells are capable of developing both the embryonic and the extraembryonic tissues. However, as they continue to divide, they...