Slight back pain and slight bleeding in early pregnancy may be caused by physiological phenomena, pre-miscarriage, ectopic pregnancy and other conditions. 1. Physiological phenomenon: early pregnancy due to changes in hormone levels in the body, the uterus increases in size, which may lead to back pain, if there is a slight bleeding, it may be implantation bleeding. 2. Pre-eclampsia: If there is insufficient progesterone in the body at the beginning of pregnancy, or if you are overworked, it may lead to pre-eclampsia, which can also lead to bleeding. 3. Ectopic pregnancy: If there is an ectopic pregnancy, then it may also lead to bleeding and back pain. Therefore, if there are abnormalities in early pregnancy, it is recommended to consult a doctor in time to avoid delaying the condition.