Fetal Growth Discrepancy: Understanding Measurement Differences & Next Steps

Question
Hi, I'm 35 and have two children.  The first date of my last period is 2/1/05.  I always have a feeling that I am a little further along that what my Dr. said, but today I had an exam and am measuring 38 weeks(she measured three times) and should be only 32 weeks.  At my last exam I was measuring 27 weeks at 25 weeks.  I have been tested for JD and that came back OK.  Both of my other children always measured me correctly.  She is sending me in for an ultrasound, but what are the factors that could cause this?  Thank you.  

Answer
Was your last period January 2 or February 1? I was not sure from your question.  If your last period started on January 2, you are now 36 weeks 2 days. If your last period started on February 1, you are now 32 weeks 2 days. If the doctor has measured you as being larger than that, you may have excess amniotic fluid, the baby may merely be large for gestational age, or you may have some element of diabetes or carbohydrate intolerance. The sonogram will confirm how far pregnant and will assess the well being of the fetus.