知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。 PGT may be done with polar bodies or an isolated blastomere of the cleavage-stage embryo, usually from the day three embryo. It may also be carried out from a sample of cells with the trophectoderm of the blastocyst-stage embryo. The benefit of a trophectoderm sample is preventing https://www.ivf.com.mx/