胚胎植入相关因子与输卵管妊娠发生的关系

异位妊娠(宫外孕)发生机理还存在较大争议,目前认为是输卵管异常导致胚胎停留在输卵管而致宫外孕的发生。输卵管中雌、孕激素受体的改变影响宫外孕的发生,同时,由于炎症或者其它因素使得输卵管一些炎症因子的改变,包括Prokineticins及其受体、激活素(Activin)A、白血病抑制因子(LIF)、整合素、白介素1(IL-1)、粘蛋白-1(mucin-1)、同源框基因(HOX)、一氧化氮(NO)等的改变,可以影响到平滑肌收缩和纤毛活动,还释放出一些胚胎植入前信号。停滞的胚胎使得子宫内膜表达一些植入前因子,从而建立输卵管种植的环境。另外,输卵管组织中免疫细胞和血管生长因子的异常也会导致宫外孕的发生。体外受精-胚胎移植宫外孕的发生稍高于正常妊娠。

Mechanism of embryo implantation in ectopic pregnancy

There is still so much controversy over the mechanism of embryo implantation in ectopicpregnancy. Current evidences suggest that tubal ectopic pregnancy results from fallopian tube dysfunction caused by embryo arrest and abnormal tubal environment. The alteration of expression of estrogen receptor and progesterone receptor in fallopian tube may influence ectopic pregnancy. Inflammation within fallopian tube including prokineticins and their receptors, activin A, leukaemia inhibitor factor （LIF）, integrin, interleukin-1（IL-1） ,mucin-1, HOX and nitric oxide（NO）,resulting from infection or other factors,appears to affect embryo transportation in fallopian tube by disrupting smoothing muscle contractility and ciliary beat activity. This inflammatory environment also releases many pro~implantation signals recognized by the arrested embryo. Furthermore, an arrested embryo may facilitate the expression of pro-implantation factors in the uterus which in turn signal the establishment of a tubal environment both suitable for and capable of implantation. Apart from these,abnormal immunocytes and angiogenesis factors in the fallopian tube have effects on ectopic pregnancy. The incidence of tubal ectopic pregnancy is slightly higher in women after in vitro fertilization treatment.