blastocyst
noun
blas·to·cyst
ˈbla-stə-ˌsist 
: the modified blastula of a placental mammal having an outer layer composed of the trophoblast
Examples of blastocyst in a Sentence
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However, fewer than 9% of the eggs created during the study went on to reach the blastocyst stage of embryo development, equivalent to five or six days postfertilization.
—
Katie Hunt, CNN Money, 30 Sep. 2025
Nine percent of the resulting embryos developed to the blastocyst stage, which is when embryos would be transferred into a woman's womb, the researchers reported.
—Rob Stein, NPR, 30 Sep. 2025
The researchers produced 82 functional oocytes (eggs) using the method, fertilized them with sperm, and found that around nine percent developed into blastocysts—the earliest stage of embryo development—by day six.
—Daniella Gray, MSNBC Newsweek, 30 Sep. 2025
However, 9 percent continued developing to the blastocyst stage of development six days after fertilization, when embryos are typically transferred to an IVF patient.
—Emily Mullin, Wired News, 30 Sep. 2025
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Katie Hunt, CNN Money, 30 Sep. 2025
Nine percent of the resulting embryos developed to the blastocyst stage, which is when embryos would be transferred into a woman's womb, the researchers reported.
—Rob Stein, NPR, 30 Sep. 2025
The researchers produced 82 functional oocytes (eggs) using the method, fertilized them with sperm, and found that around nine percent developed into blastocysts—the earliest stage of embryo development—by day six.
—Daniella Gray, MSNBC Newsweek, 30 Sep. 2025
However, 9 percent continued developing to the blastocyst stage of development six days after fertilization, when embryos are typically transferred to an IVF patient.
—Emily Mullin, Wired News, 30 Sep. 2025
See All Example Sentences for blastocyst
Cite this Entry
“Blastocyst.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/blastocyst. Accessed 20 Oct. 2025.
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blastocyst
noun
blas·to·cyst
ˈblas-tə-ˌsist
: the modified blastula of a placental mammal
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