A woman does not notice any change in her uterus at six weeks of pregnancy, according to Mayo Clinic. Fundal height, or the measurement of the pubic bone to the top of the uterus, may not be measured by a health care provider until the middle of the second trimester.
Spotting or cramping, a missed period, swollen or tender breasts, fatigue, and nausea are signs of early pregnancy, states WebMD. However, not all women experience all of these signs. Many women do not realize they are pregnant until between 6 and 8 weeks' gestation. Typically the first sign is a missed period.