Hi Kathy,
You've gotten some really good replies already, but I'll just throw in my own 2 cents worth. I'm 37, unexpectedly pregnant w/ my 3rd baby and already have 1 boy and 1 girl at home. So we weren't trying to get pregnant, but obviously didn't try hard enough not to either.;-)
My ob explained to me all the different types of testing, etc, gave me all that paperwork, and in the end I decided to go ahead and have the amnio. Since I made that decision, I didn't have to do all the other prior testing. The one pro of amnio that my OB told me is if one has the prior testing and there is something, sometimes the only way to try and clarify is to get the amnio anyway. So I decided to go ahead and just do the amnio. I was nervous in general, not necessarily b/c of the amnio, but just b/c I'm an older mom. Last year in my workplace, there were many incidents of problematic pregnancies w/ gals YOUNGER than 35 anyway!
For us, the results of the amnio would not have altered what we would do. In California, you have to do the amnio by 20 wks in case you want to exercise your options. For me, I just wanted to know and be prepared.
When we went to our appt (I was at 19 1/2 wks), first there was our genetic counseling (btw some of those questions are kinda funny). Then there was the ultrasound, first by a nurse (I think) and then the doctor came. Both people said that the baby looked fine and that the baby appeared to be a boy. Then the doctor said that he saw nothing in the ultrasound that made him think I was at any higher risk for anyhing and asked if I still wanted to do the amnio. I said yes.
Then came the part that my wussy DH wouldn't watch - sticking the needle in my stomach. The doctor did it left of my bellybutton, and it kinda stung and he had to w/draw a vial of fluid (that I expected to be milky colored or opaque but was actually clear). Afterwards, the doctor said no sex for 48 hrs (and my DH was like "no problem!"), only light walking, no lifting of anything, and to sleep on my side. Apparently the risks of the amnio have to deal w/ leakage from the needle insertion point and infection of the amniotic fluid and what that would do to the little baby. I took a couple of days off work to be extra careful and just took it easy, which included NOT carrying around my almost 3-year old princess.
The genetic place called me exactly 10 days later to inform me that the baby is definitely a boy, and that the results were good. (i.e. right number of chromosome pairs, etc). So I am very relieved.
Hope this post wasn't too long for you, but I really understand what you're going thru and hope this helps a little.
Good luck w/ whatever you decide to do!
Belle