First, there will be a cessation of menstruation, followed by a brief period of amenorrhea, and then irregular vaginal bleeding will occur. This vaginal bleeding is usually light and droplet-like, and the color is dark red. Additionally, most women will experience pain on one side of the lower abdomen, which manifests as a distension pain. At this time, because the ectopic pregnancy in the fallopian tube has not ruptured, the enlarging embryo causes the fallopian tube to expand, leading to spasms of the tube, and thus these symptoms occur. If the condition continues to progress, the fallopian tube may rupture, resulting in acute and severe pain on one side of the lower abdomen.