Symptoms of an ectopic pregnancy typically start fairly early in pregnancy, usually between the 4th and 12th weeks. Some sources specify that symptoms often begin around 6 to 7 weeks after the last menstrual period. Early symptoms may resemble normal pregnancy signs, such as a missed period, breast tenderness, and nausea, but soon more specific symptoms emerge. These include abnormal vaginal bleeding, abdominal or pelvic pain typically on one side, and sometimes shoulder pain due to internal bleeding. In some cases, symptoms might not be noticed until an emergency such as a rupture occurs, causing severe pain and heavy bleeding requiring immediate medical attention.