Understanding HCG Levels & Early Pregnancy - A Medical Perspective

Question
I am 38 yo with 4 children.  The date of my last period was Nov. 2, 2004 with a positive pregnancy test Nov. 30th.  Just went for quantitative HCG Jan. 25th.  Nurse said I was only 5.5 weeks along.  I haven't had any bleeding or serious cramping and I'm wondering what could be going on.  Can the HCG levels vary that much in the normal range that she could mistake the dates?  She wouldn't schedule an appointment with OB until March 2nd.  Thanks!

Answer
It is difficult to tell how far pregnant you are merely from the value of your Beta HCG results. If your last period started on November 2, you should now be 12 weeks gestational age (especially if you had a positive pregnancy test on November 30. The range of HCG value at this time in pregnancy is 10,000 -100,000. You did not mention what your value was. If you are really 12 weeks pregnant (from the first day of your last period) a sonogram will show a fetus and a fetal heartbeat at this time. At 5.5 weeks gestation, HCG values also range from 10,000 - 100,000, so it is difficult to say how far you are basaed on HCG values. HOwever, if you were only 5.5 weeks pregnant, a sonogram would only show a gestational sac but no fetus or fetal hearbeat until you reach, at least, 6 weeks gestational age. Get a sonogram and you will know exactly how far you are. Good Luck.