3 doctors weighed in:

When you are expecting do the dr. Usually go by your last day of your last cycle or your first day of your last cycle?

3 doctors weighed in
Dr. Chevies Newman
Obstetrics & Gynecology
1 doctor agrees

In brief: First

First day of last menstrual period is the starting point.

In brief: First

First day of last menstrual period is the starting point.
Dr. Chevies Newman
Dr. Chevies Newman
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Dr. Robert Kwok
Pediatrics
1 doctor agrees

In brief: First day

Weeks of pregnancy (weeks of gestation) are counted from the first day of the last cycle, and that day is called lmp.
If the lmp is unknown, but an ultrasound is able to tell how many weeks after conception the fetus is, then the lmp is estimated to be 2 weeks before the ultrasound-determined conception date.

In brief: First day

Weeks of pregnancy (weeks of gestation) are counted from the first day of the last cycle, and that day is called lmp.
If the lmp is unknown, but an ultrasound is able to tell how many weeks after conception the fetus is, then the lmp is estimated to be 2 weeks before the ultrasound-determined conception date.
Dr. Robert Kwok
Dr. Robert Kwok
Thank
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