Q: Good day doctor. Can you please help me? I need clarity. If you had an implantation bleeding and found out that you are pregnant, how do you calculate weeks of pregnancy? Do you start from last period or the day of implantation day? Please help. Thank you
A: Implantation bleeding is typically a small amount of light bleeding that occurs about 10 to 14 days after conception. This is thought to be due to implantation as the fertilized egg implants itself in the uterus (womb). This usually occurs in early pregnancy, close to or about the same time as the menstruation would be seen and is thus often mistaken for a period. But, it is usually lighter than menstrual…typically without clots. It would stop on its own and does not require further treatment. If the bleeding is heavier, associated with cramps or any other complication, please see your doctor. As a rule of thumb really, any bleeding in pregnancy should be investigated as they may be due to more serious conditions like ectopic pregnancy, miscarriage and infections.
Now, as to dating pregnancy, this is best done with the use of the last menstrual period – that is the first day of the woman’s last normal menstrual flow. However, if she is not sure of her dates, then a scan can be used. To date pregnancy, a first trimester scan gives the most appropriate approximation. The earlier it is, the more accurate it is likely to be.
I hope this helps 🙂