It can be frightening, however, it doesn’t always mean you could be experiencing a miscarriage. Bleeding during pregnancy, especially during the first trimester, is more common than during 5th week and 8th weeks. there are several causes of bleeding during pregnancy: 1. implantation bleeding - this is when a fertilized egg attaches to the uterine lining and can result in light spotting or streaks of blood. 2. breakthrough bleeding - this results if the hormone levels are not yet high enough to stop your period even though you are pregnant.it usually appear at around 4, 8 and 12 weeks of pregnancy. 3. threatened or actual miscarriage 4. ectopic pregnancy - this is when the fertilized egg implants outside the uterus. 6. Placenta Previa - it is a painless vaginal bleeding due to abnormal implantation of the placenta sometimes near the cervix. 7. uterine fibroids - masses found inside or outside the utrerus.