Fetal Age Vs Gestational Age Please Help

10 Replies
tritty - June 27

so i'm so totally confused. i had a dating ultrasound today because i wasn't sure how far along i was (was on bcp's and had some irregular periods). anyhow, the ultrasound dated the fetus at 7w 3d. so, to get the gestational age do i add 2 weeks to that so i'm really 9w 3d ? the reason i don't know is because they ultrasound tech told me that my EDD is feb. 10, 2007 but if I count back 9 w 3 d from now ( April 22, 2006)and count that as the first day of my LMP then i'm getting January 27, 2007 as my due date. anyone have any insight? i'm totally confused!

 

mcatherine - June 27

You don't add two weeks. You're 7 weeks 3 days and your EDD is the February date. Congratulations!!!

 

Deb - June 27

I agree, the ultrasound date means that YOU are 7weeks 3 days pregnant.

 

tritty - June 27

where i'm confused is that i know that the baby is 7 weeks 3 days (from the date of conception) but then why on all these due date calculators do you start counting from the first day of your last period. so by the time you're one week pregnant (the fetus is one week) you consider it 3 weeks gestational age. that's where i'm confused.

 

tritty - June 27

maybe i get it now. i think you use the first date of lmp as an estimate of how far along you are. BUT... when you have an ultrasound you find out exactly how far you are. so people who don't have an ultrasound so soon wouldn't know exactly how far they are but since i had one i have an exact date?!? am i right or just confusing myself more?

 

mcatherine - June 27

Ultrasounds figure in the 2 weeks pre-conception. Meaning you actually conceived around 5.5 weeks ago.

 

kvilendrer - June 27

That's the only way they can calculate a due date because not everyone ovulates around the same time. They don't know exactly when you ovulated, so that's the only date they have to go by.

 

mcatherine - June 27

Ovulation isn't exact and it can get really confusing. I've had to have dating ultrasounds done for two pregnancies and it was explained to me that the two weeks pre-conception were figured in. At six weeks, all normal pregnancies look the same - so your baby looked just like any other baby would at 7.3 weeks - including those two weeks when you weren't actually pregnant yet.

 

tritty - June 27

i just got off the phone with the doctor and they said that they only measure the fetal age and not the gestational age (which is odd considering doctors go by weeks gestation)

 

tritty - June 27

mccatherine.... if you were right and i conceived 5.5 weeks ago (so the fetus would be 5.5 weeks) isn't that young to have arms/ legs and a strong heartbeat? i've been reading a lot of books and what i saw on the ultrasound it just about where 9 gestational weeks would be. the girl that did the ultrasound said they had a wierd way of doing it.... i don't know.... i guess i'll wait to talk to my doctor.

 

mcatherine - June 27

All doctors do things differently. That was my explanation. I know it goes by weight and length - but talk to your doctor - hopefully they can make sense of it for you! It does make it confusing when you want to read about what week you're in, but don't know what chapter to read! I do suggest in that case to read Your Pregnancy Week by Week because it has fetal AND gest. age to go by in each chapter.

 

ADD A COMMENT:


You must log in to reply.

Are you New to the forum? Sign Up Here! Already a member? Please login below.

Forgot your password?
Need Help?
New to the forum?

Sign Up Here!


Already a member?
Please login below.





Forgot your password?
Need Help?