The doctors are confusing me

[RT200]

Hello
after 18 months of trying and 1 confirmed miscarriage and 1 possible miscarriage - I am finally pregannt! I am elated! I had to take Clomid for almost 12 months to help me ovulate and my double/triple whammy is I have PCOS and am Type 2 Diabetic so I also take Metformin.
1) According to my last period I should be 8 weeks along this Thursday but last last Thursday I had my first ultra-sound to elminate some cramping I had been experiencing (which felt like the beginnings of a bad period - but has thankfully turned out to be nothing - just the uterus strateching - the sac looks round and fine!!), the specialist said the measurements only added up to about 6 and a half weeks along. How do these dates/measurements not add up and have just over a week out?
2) Also - I am still taking Metformin as I am told it elminates/decreases the chances of miscarriage in diabetic women by almost 80%. However both my gyno and my very own endocronologist are saying to stop this once i reach 16 weeks. However, I have heard stories of women who did so (stopped Metformin) and miscarried at just after 4 months.

does anyone have any advice or stories they can share regarding my 2 questions?

Thanks
RT200

[chantal21]

First of all congrats!! =) Were they able to see a heartbeat at your u/s? As far as dating the pregnancy....u/s are pretty accurate in the first trimester. You could have just ovulated later than you thought you did. That happens a lot.
As far as your other question, I am not sure...hopefully someone on here can help you out with that. I hope everything goes well for you this time!!

[JJety]

My memory is fuzzy, but I think women tend to ovulate later in their cycle when taking Clomid, so this probably accounts for the time inaccuracy.  The u/s also has a margin of error of about 5-7 days.  Were they able to see a heartbeat yet?  Are they drawing blood to monitor your hcg levels?  I'm ssuming they'll also give you another u/s soon...?  If they give you another one next week, at 7.5 weeks along, you should see a heartbeat.

I know nothing about Metformin, sorry.

Good luck and congratulations!!!