Why do i always have a menstrual cycle after conception? i have a period and then i don't have any more until after i give birth.

Bleeding: Bleeding does not mean you are having a menses. Menses is the loss of blood from the uterus when you are not pregnant and your hormones fall. Bleeding during pregnancy is very common and can have a number of sources including the rectum, cervix and just the stretching of the uterus to accommodate the growing baby. Bleeding without cramping can be normal.