Ola Bolarinde, Li Tin-Chiu
Department of Obstetrics and Gynaecology, Sheffield Teaching Hospital NHS Foundation Trust, Sheffield, UK.
Curr Opin Obstet Gynecol. 2006 Aug;18(4):440-5. doi: 10.1097/01.gco.0000233940.82296.49.
Embryo implantation remains the rate-limiting step in assisted conception programmes. Factors affecting the interactions between blastocyst and endometrium are subjects of current research and, sadly, have also been the subjects of much confusion. This review aims to present current thinking on factors affecting embryo development, endometrial receptivity during and around the implantation window and the evidence for and against various proposed treatment options
Age-related aneuploidies of the sex chromosomes and several other autosomes are now thought to adversely affect oocyte and embryo quality, leading to repeat in-vitro fertilization failures. Several small controlled trials have suggested improvements in clinical outcomes following preimplantation screening and blastocyst transfer for aneuploidy in older women. These are, however, very costly, wasteful of embryos and do not appear beneficial after the age of 40 years. Factors influencing endometrial receptivity remain largely unresolved. New technology using microarrays for gene expression profiling and progesterone receptor polymorphism may shed more light in the near future.
Giant strides have been made in studying the causative factors of implantation failure, but these have not been matched by therapeutic solutions. Many proposed interventions are of unproven value, yet can have harmful side-effects.
胚胎着床仍然是辅助受孕计划中的限速步骤。影响囊胚与子宫内膜相互作用的因素是当前研究的课题，遗憾的是，这些因素也一直存在诸多混淆之处。本综述旨在阐述当前对影响胚胎发育、着床窗口期及前后子宫内膜容受性的因素的看法，以及支持和反对各种提议治疗方案的证据。
现在认为，与年龄相关的性染色体及其他几条常染色体的非整倍体对卵母细胞和胚胎质量有不利影响，导致体外受精反复失败。几项小型对照试验表明，对老年女性进行植入前筛查和非整倍体囊胚移植后，临床结局有所改善。然而，这些方法成本非常高，浪费胚胎，且在40岁以后似乎并无益处。影响子宫内膜容受性的因素在很大程度上仍未得到解决。利用微阵列进行基因表达谱分析和孕酮受体多态性的新技术可能在不久的将来提供更多线索。
在研究着床失败的致病因素方面已经取得了巨大进展，但治疗方案却未能与之匹配。许多提议的干预措施价值未经证实，但可能有有害的副作用。
