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n. pl. pre-em·bry·os
A fertilized ovum up to 14 days old, before it becomes implanted in the uterus.

pre-em′bry·on′ic (-ŏn′ĭk) adj.


(Biology) the structure formed after fertilization of an ovum but before differentiation of embryonic tissue
References in periodicals archive ?
The Department of Health wants to change the law so a fertilised egg with damaged DNA could be treated at the pre-embryo stage to avoid potentially deadly disorders such as lung and heart problems.
After the procedure, some women were told their eggs were "unsuitable" for fertilization, and some women were told their eggs had been fertilized and the pre-embryo had been "frozen for her future use.
The harvesting of stem cells is immoral because it necessitates the destruction of the pre-embryo at the blastocyst stage, which is regarded by many as a human being with an inalienable right to life.
Jasanoff describes the concept of a pre-embryo as being coproduced out of a complex mixture of pragmatism, empiricism, and trust in experts.
Therapeutic cloning is another scientific process where after the fusion and development of pre-embryo, eggs are not planted in a womb, rather they are killed.
Advances in the technology of freezing and restoring gametes (sperm or ova) and pre-embryo have had a significant impact on reproductive technology.
Wolter, Reflections on the Moral Status of the Pre-Embryo, 51 THEOLOGICAL STUDIES 603, 610-14 (1990).
Wolter, "Reflections on the Moral Status of the Pre-Embryo," Theological Studies 51 (1990): 603-26.
Just as pre-Christians are not Christians and pre-marital sex isn't sex in marriage, so too a pre-embryo sounds like a non-embryo.
As a case in point, Suadeau offered the term pre-embryo, which he said was coined in England in the 1990s to justify research on human embryos.
On the first issue, are these embryos human life--well, one researcher told me he believes this five-day-old cluster of cells is not an embryo, not yet an individual, but a pre-embryo.