While not all women experience early pregnancy symptoms, during the first few weeks of pregnancy some pregnant women experience sudden spotting and cramping, increased soreness of the breasts, darkening of the areola and sudden fatigue. However, these symptoms can be caused by conditions other than pregnancy; the only way to determine for sure if conception has occurred is to take a pregnancy test.
Implantation bleeding occurs anytime between six to 12 days after fertilization and is caused when the fertilized egg attaches itself to the uterus. Implantation bleeding is sometimes accompanied by a white vaginal discharge, which is due to the thickening of the vagina's wall, a process triggered by conception.
Spotting and cramping may occur, which resemble the start of a period. Increased hormonal levels accompanying conception also cause the breasts to change, becoming heavier, more tender, fuller or swollen. High levels of progesterone also cause increased fatigue, usually beginning about one week after conception. However, increased fatigue can also be attributed to a variety of causes such as low blood sugar and low blood pressure. WebMD recommends plenty of rest and increasing iron intake in order to combat fatigue. The body can take several weeks to adjust to pregnancy.