Slight bleeding or cramping For some women, a small amount of spotting or vaginal bleeding is one of the first symptoms of pregnancy. Known as implantation bleeding, it happens when the fertilized egg attaches to the lining of the uterus — about 10 to 14 days after fertilization. This type of bleeding is usually a bit earlier, spottier and lighter in color than a normal period and doesn't last as long. Some women also experience abdominal cramping early in pregnancy. These cramps are similar to menstrual cramps. Nausea with or without vomiting Morning sickness, which can strike at any time of the day or night, is one of the classic symptoms of pregnancy. For some women, the queasiness begins as early as two weeks after conception. Nausea seems to stem at least in part from rapidly rising levels of estrogen, which causes the stomach to empty more slowly. Pregnant women also have a heightened sense of smell, so various odors — such as foods cooking, perfume or cigarette smoke — may cause waves of nausea in early pregnancy.