Pregnancy symptoms differ from woman to woman and pregnancy to pregnancy; however, one of the most significant pregnancy symptoms is a delayed or missed menstrual cycle. Understanding the signs and symptoms of pregnancy is important because each symptom may be related to something other than pregnancy.  Some women experience signs or symptoms of pregnancy within a week of conception. For other women, pregnancy symptoms may develop over a few weeks, months, or may not be present at all. The most common pregnancy signs and symptoms are noted below. If you have been sexually active and are experiencing any of these symptoms, it is important to take a pregnancy test.