During the second and third month of pregnancy, gums may begin to become a bit swollen, irritated and may even bleed a little. Sensitivity and bleeding of the gum tissue is thought to be caused from rises in pregnancy hormones, particularly progesterone, in addition to increased blood flow to the mouth. This symptom may get worse as your pregnancy progresses. Bleeding and inflamed gums can also be a sign of something else, including Leukemia, vitamin deficiencies, bleeding disorders and gingivitis. This symptom may also occur when using oral contraceptives.