how do u calculate the first date of "pregnancy"?

hi doc.

I'm confused about calculating how far I would be If I were pregnant.

Do I start counting from the day that I ovulated or do I start counting since implantation was completed.

I've ovulated on Nov 23,2009 as per my monitor.So If I'm pregnant now ,am I two weeks pregnant ?

Or if implantation happens in a week,that would make me one week pregnant.

I do have weak line on HPT.

baby dust

[Elaine Brown, MD]

HI!
YAY!!!!!
Doctors calculate from the first day of the last menstrual period.  We use this because there could often be more than one opportunity for the conception date.  Especially if you were "trying".
If you calculate from your LMP, you are probably about 4 weeks pregnant.
Many of the pregnancy wheels will also have a conception day line, about two weeks after the LMP line.  If you use this line, you will still be considered to be 4 weeks pregnant.  It is probably best to go with this method of calculation because that is how your due date will be calculated, and if you don't calculate this way, you will be off by 2 weeks for the whole pregnancy!
Good luck!
Dr B