Plachot M
Baillieres Clin Obstet Gynaecol. 1992 Jun;6(2):327-38. doi: 10.1016/s0950-3552(05)80090-2.
Only about 10% of embryos obtained after in vitro fertilization (IVF) are able to implant after transfer in utero. Detecting the viable embryos is therefore the prerequisite condition to increase the overall efficiency of the technique. Zygote and embryo morphology is partly related to their viability. Indeed, fertilized oocytes with a timely fertilization and pronuclear growth, leading to embryos with equally sized blastomeres reaching at least the 4-cell stage about 42 h after insemination, have the best chance of implanting. The metabolic approach, although requiring sensitive microassays, seems promising. Indeed, in a small series 100% of the pregnancies were predicted when the level of interleukin 1-alpha was > 60 pg/ml and the suppressive level (antiproliferative activity using tumour cell lines) was > 20% in the supernatant of transferred embryos. Lastly, invasive assessment of the chromosome status of embryos should allow us in future to discard severely abnormal embryos, thus increasing the success rate of IVF.
体外受精（IVF）后获得的胚胎中，只有约10%能够在子宫内移植后着床。因此，检测存活胚胎是提高该技术整体效率的前提条件。合子和胚胎形态部分与其活力相关。实际上，受精及时且原核生长正常的受精卵，会发育成卵裂球大小相等的胚胎，在授精后约42小时至少达到4细胞期，这类胚胎着床的几率最大。代谢方法虽然需要灵敏的微量分析，但似乎很有前景。确实，在一个小样本研究中，当移植胚胎的上清液中白细胞介素1-α水平>60 pg/ml且抑制水平（使用肿瘤细胞系的抗增殖活性）>20%时，100%的妊娠得到了预测。最后，对胚胎染色体状态进行侵入性评估应能使我们在未来舍弃严重异常的胚胎，从而提高体外受精的成功率。
