Has anyone passed out while pregnant? I had a scare the other day at work. I'm 17 weeks pregnant and it's my first pregnancy. I went to the ER and they ran a bunch of tests and made sure the babies heart beat was ok. The conclusion was that I was dehydrated. Drinking more fluids especially water is so important during pregnancy. They said it's really important to listen to your body. If you need to rest than rest. Lesson learned.