I had my last period on December 21,2011 and I found out that I am pregnant just this January 2012. How will I know if how many months I am pregnant right now? Thank you.

Hi JohnKate,

Pregnancy is best marked by weeks instead of months. Generally the weeks start with the first day of your last period and may be altered after you have a scan (this is because you usually aren't pregnant until a week or two after you period). Going from December 21, you would be considered a little over 8 weeks pregnant at this point.

It is a best educated guess. So you know it happened sometime after your last period, till you tested pos ( or till you missed the next period) So it would have happened end of Dec or Jan.