For me personally, it was essential for me to have transvaginal (TV) scans until I was 14w as I have a retroverted uterus (i.e. tilted back). Having a 'retro ute' (LOL) makes it particularly hard for anything to be seen externally, full bladder or not as it is in a different position to 90% of the female population.
I have had a number of scans over the past 6 - 8 years due to some gynaecological issues such as an ovarian cyst etc etc and my m/c's last year, and each and very time, they have had to be TV scans. I can tell you that they are much clearer than external ones, however since I reached the 14w mark when the baby was able to be detected externally, I have been having external scans.
As Kelly said, you don't HAVE to have a TV scan if you're not comfortable with it - you always have the right to refuse this. Now I know this is going to sound really gross, but at scans that I have had at u/s clinics, I was asked if I wanted to "insert the probe"....i.e. you can do it or the sonographer can do it. I can only assume that this is most likely a standard practice - so don't feel that if you do agree to have an internal scan that you can't have control over this aspect IYKWIM - in any event, you should at least ask if you would be more comfortable inserting it yourself. However, all of my u/s for this PG (bar 1) have been done by my OB, and he inserted the probe himself, but it actually didn't bother me since I've had so many of the damn things over time (gawd...it's bad thinking that I have actually become used to those retched things!)
HTH Snowy...I know it can all be a bit scary and yucko!
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