It is not normal for a woman to have a small amount of dark red menstruation after pregnancy. Normally a woman will not have a period after pregnancy. If there is a small amount of menstruation, i.e. a small amount of vaginal bleeding, it is mostly due to a preterm miscarriage after pregnancy, when the color of the bleeding is usually dark red. The woman needs to go to the hospital for gynecological ultrasound, blood tests for HCG and progesterone, and bed rest and progesterone medication for fetal preservation in case of preterm miscarriage. If a woman’s vaginal bleeding resembles menstruation, an ultrasound may be performed and the pregnancy may be terminated if there is embryonic abortion or inevitable miscarriage.