Smart Y C, Fraser I S, Clancy R L, Roberts T K, Cripps A W
Fertil Steril. 1982 Feb;37(2):201-4.
Measurement of early pregnancy factor (EPF) by the rosette inhibition test was performed on serum samples from 14 women using intrauterine devices (IUDs). Serial blood samples taken during the luteal phase of 23 cycles demonstrated in six of the cycles a transient appearance of EPF during the 6- to 8-day period following ovulation. In contrast, no EPF activity was found in sera obtained from women in whom fertilization was prevented, either by sexual abstinence or tubal ligation. These observations support the postulate that the IUD functions by the prevention of implantation of the fertilized ovum, rather than by preventing fertilization.
采用玫瑰花结抑制试验对14名使用宫内节育器（IUD）的女性血清样本进行了早孕因子（EPF）检测。在23个月经周期的黄体期采集的系列血样显示，其中6个周期在排卵后6至8天出现了EPF的短暂出现。相比之下，在通过禁欲或输卵管结扎防止受精的女性血清中未发现EPF活性。这些观察结果支持了这样一种假设，即宫内节育器的作用是防止受精卵着床，而不是防止受精。
