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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While critics warn that the data is preliminary, Merhi’s own studies have suggested PRP may improve blastocyst euploidy rates—raising the chance of embryos with normal chromosomes.
—
Matt Emma, USA Today, 11 Dec. 2025
There’s also the waiting period—waiting to see if and how many eggs would fertilize and how many would make it to the blastocyst stage, which happens about five to six days after the sperm fertilizes the egg.
—Anna Halkidis, Parents, 9 Dec. 2025
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
See All Example Sentences for blastocyst
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Matt Emma, USA Today, 11 Dec. 2025
There’s also the waiting period—waiting to see if and how many eggs would fertilize and how many would make it to the blastocyst stage, which happens about five to six days after the sperm fertilizes the egg.
—Anna Halkidis, Parents, 9 Dec. 2025
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
See All Example Sentences for blastocyst
Cite this Entry
“Blastocyst.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/blastocyst. Accessed 23 Dec. 2025.
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blastocyst
noun
blas·to·cyst
ˈblas-tə-ˌsist
: the modified blastula of a placental mammal
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