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I wouldn't say I'm "against" ultrasound, as it does have valid medical uses during pregnancy. I do think that it is overused and shouldn't be considered routine. There are potential risks with it's use and it seems that most of the information gained from ultrasound is very open to interpretation. In other words, the results are not definite. It is nice to have the peace of mind that having a "good" ultrasound can provide, but the other side of the coin is that mothers worry about negative, often incorrect, information that is given through ultrasound. I can't remember the number of threads here that I have read in which a mother is in tears because her doctor has informed her that her baby has or might have certain issues. A lot of the time, the baby turns out to be perfectly fine.
It has been a long time since I researched this, but apparently Doppler ultrasound is stronger and potentially more harmful than the other type of ultrasound. For that reason, I also prefer to avoid Doppler use. For the most part, it seems that Doppler use in pregnancy, as opposed to its use in birth, is just to check that baby is alive! Most of the time, this is not necessary. Once the mother can feel movement, I personally don't know of any reason to routinely use Doppler. If there are concerns, of course that is different, but I imagine that regular ultrasound or continuous monitoring would be more helpful in such a case anyway.
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Despite my feelings about ultrasound, I've had one in each of my pregnancies so far. With my first, I had one ultrasound because of vaginal bleeding (thank G-d, everything was fine). I also heard the heartbeat with the hand-held Doppler maybe 4 times and intermittently in labor.
With my second pregnancy, I really hoped to avoid ultrasound. Again, I had vaginal bleeding, but I waited it out until I felt sure that something was wrong (the bleeding was getting heavier and I was cramping, etc.). I knew there was nothing that could be done to prevent a first trimester miscarriage, so when I finally had the ultrasound I was mostly confirming what I already knew, even though I hoped for the best. It turned out I was right (no heartbeat, baby small for dates), and I miscarried that night after having the ultrasound. I ended up having another ultrasound to confirm that the "products of conception" had all been passed.
With my third pregnancy, I had hyperemesis and needed to go to the emergency room for IV rehydration. They didn't even tell me they were ordering an ultrasound for me; they just wheeled me to the ultrasound room! Then they told me that they needed to check if I was having twins or a molar pregnancy, because apparently hyperemesis is more common in those cases. When I heard "twins", I couldn't help but consent to the ultrasound!

I was really hoping to see two babies.

I didn't have any Doppler with that pregnancy. I had a UC, so I didn't have any during the birth, either.