Impact of early cleaved zygote morphology on embryo development and in vitro fertilization-embryo transfer outcome: a prospective study.
ABSTRACT To evaluate the impact of the first division morphology on embryo development and IVF-embryo transfer outcome.
Teaching hospital, France.
All zygotes from 201 couples were checked for early cleavage. We defined as "even," early cleaved (EC) zygotes with 2 cells of even size; as "uneven," EC zygotes with 2 cells of uneven size; and as "fragmented," EC zygotes with more than 20% fragmentation rate. Day 2 embryo quality was assessed as "top" embryo or "non-top," with the evaluation of multinucleated blastomeres.
Day 2 embryo quality, pregnancy and implantation rates.
Among EC zygotes, 59.1% were even, 13.0% were uneven, and 27.9% were fragmented. Even EC yielded more "top" embryos and less multinucleated blastomere embryos than uneven EC (77.0% vs. 46.3%) and fragmented EC (77.0% vs. 13.9%). The 125 double embryo transfers that comprised at least one embryo derived from even EC zygote led to higher pregnancy rate (PR) (64.0% vs. 43.4%) and implantation rate (42.0% vs. 27.6%) compared to the 76 double embryo transfers with embryos derived from breakdown or 2PN zygotes.
The morphology of the early cleaved zygote is involved in embryo development. Evaluation of this morphology is an effective and valuable method of assessing the embryo quality.
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ABSTRACT: Time-lapse imaging is increasingly applied as an adjunct to reproductive medicine. The gained information of the morphological and morphokinetic variables before the onset of transcription are supposed to be good predictors for the selection of the best embryo for transfer and are often seen in line with clinical outcomes. This retrospective case series investigated the outcome of transferred blastocysts that did not fulfil the proposed embryo scores at early cleavage or at later stages of development. The observations were made by time-lapse imaging. This study reports the birth of 16 healthy children after day-5 blastocyst transfer, of which at least one of the transferred embryos originated from deviant morphology and/or kinetic cleavage patterns. This case series suggests that some blastocysts derived from embryos with poor conventional morphological score and/or suboptimal morphokinetics can be successfully transferred and might result in live births. Such results might raise awareness that discarding embryos based only on early events is not a suitable approach to give patients the chance to conceive. In conclusion, to date only the transfer of viable embryos after culturing them until day 5 guarantees optimal embryo selection and helps to prevent embryo wastage.Reproductive biomedicine online 01/2014; · 2.68 Impact Factor
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ABSTRACT: The purpose of the review is to summarize recent developments in time-lapse technologies and early embryo morphokinetics and to discuss their impact on current clinical outcomes. Contemporary embryo culture and selection methodologies that are based on classical morphology are clearly limited in providing the most suitable embryo for a successful pregnancy. Noninvasive observation of embryo development by capturing the images with a time-lapse device has recently been proposed to be a better method of embryo viability assessment. Such methodologies have been shown to increase the quality and the quantity of information on the viability without disturbing the culture conditions. Commercial availability of different time-lapse devices for human embryos facilitated the use of morphokinetics as an additional tool in human embryo selection. The application of such technologies has already shown positive results on clinical outcome by increasing our scope of traditional embryo selection, leading to higher implantation and clinical pregnancy rates. Additional benefit can come from the less-disturbed incubation environment that is created by all-in-one incubators. Such devices can also be very important research tools in order to observe and analyze the effect of different patient-specific or clinical conditions on embryo development parameters that are not available through classical embryo scoring.Current opinion in obstetrics & gynecology 04/2014; · 2.49 Impact Factor