Rijnders P M, Jansen C A
Department of IVF, Obstetrics and Gynaecology, Reinier de Graaf Groep, Voorburg, The Netherlands.
Hum Reprod. 1998 Oct;13(1O):2869-73. doi: 10.1093/humrep/13.10.2869.
The transfer of blastocysts has been associated with a very high implantation rate. However, not all embryos achieve the blastocyst stage. Our study was set up to demonstrate whether embryo morphology on day 3 predicts subsequent blastocyst formation. A prospective study was carried out in 48 patients with a mean of 2.9 failed in-vitro fertilization (IVF) attempts. In this new cycle, the morphology of the embryos on day 3 was noted. After pre-selection of the embryos which would have been transferred on day 3, all embryos were cultured individually and allowed to develop further until transfer on day 5. The clinical pregnancy rate per transfer was 46%, and the overall implantation rate was 24%. When only blastocysts were transferred the pregnancy rate was 53% with an implantation rate of 30%. Thirty-nine per cent of all embryos reached the blastocyst stage on day 5; 47% of class 1 and 2 embryos (good quality) in contrast to 21% of class 3 and 4 embryos (poor quality). Respectively 45% of class 1 and 2 embryos and 69% of class 3 and 4 embryos arrested in development or degenerated. Only 51% of the embryos that were transferred on day 5 had been pre-selected for transfer on day 3. In conclusion, it appears that the predictive value of embryo morphology on day 3 for subsequent blastocyst formation is limited.
囊胚移植与非常高的着床率相关。然而，并非所有胚胎都能发育到囊胚阶段。我们开展这项研究是为了证明第3天胚胎的形态是否能预测随后的囊胚形成。对48例平均有2.9次体外受精（IVF）失败尝试的患者进行了一项前瞻性研究。在这个新周期中，记录了第3天胚胎的形态。在预先选择原本会在第3天移植的胚胎后，所有胚胎单独培养，使其进一步发育直至第5天移植。每次移植的临床妊娠率为46%，总体着床率为24%。仅移植囊胚时，妊娠率为53%，着床率为30%。所有胚胎中有39%在第5天发育到囊胚阶段；1级和2级胚胎（质量好）中有47%，相比之下3级和4级胚胎（质量差）中只有21%。分别有45%的1级和2级胚胎以及69%的3级和4级胚胎发育停滞或退化。第5天移植的胚胎中只有51%是在第3天预先选择用于移植的。总之，第3天胚胎形态对随后囊胚形成的预测价值似乎有限。
