Vaginal bleeding can occur anytime in pregnancy.   It is relatively common and can occur during any trimester from conception (when the egg is fertilized) till the end of the pregnancy. Vaginal bleeding during pregnancy happens to about 15–25% of pregnant women especially during the first trimester (first 14 weeks) of pregnancy.
However, bleeding can also occur in the second and third trimester of pregnancy, so it is important to know the sign of a possible complication and get checked by an Obstetrician Gynaecologist to make sure you and your baby are in safe hands.
Abnormal vaginal bleeding in pregnancy is defined as bleeding during pregnancy that is usually as heavy as the bleeding you have on the second day of your menstrual period.