While it is quite common for spotting to occur during the course of a pregnancy, it should not be ignored. It is always better to consult your gynecologist. Give your doctor a description of the amount of blood you have lost, how you are feeling, whether the bleeding was persistent and whether you experienced any pain or fever. This article provides a list of possible reasons for spotting during pregnancy: http://www.bellybelly.com.au/pregnancy/bleeding-during-pregnancy/ Do schedule an appointment with your doctor for a peace of mind. Take care!
It is normal to experience spotting during pregnancy. However, to have a peace in mind you should immediately call up or visit your gynae to examine further what is the cause. Normally gynae will prescribe dupston pill to stabilise the pregnancy.
My cousin experienced spotting and heavy bleeding in week 13 as well. Her gynae just asked her to monitor. Her baby turned out fine and healthy.
thanks