The symptoms of a UTI are the same as they were before you got pregnant, and you will probably recognize that burning feeling of a urinary tract infection. Your uterus now sits right on top of your bladder, putting its full weight right where it hurts most, so the symptoms might be more heavy. When you notice the symptoms, you should see your doctor for a urine culture to confirm your symptoms are caused by a urinary tract infection. You should make sure that you don't leave a urinary tract infection untreated while you're pregnant. As always, untreated UTIs can lead to kidney infections, which you really want to avoid in any circumstances, I've had one and it was possibly the worst pain i ever felt including giving birth twice! Kidney infections can lead to preterm labor as well, so are especially dangerous when you are pregnant.
Once you have been diagnosed with a urinary tract infection, your doctor will prescribe you a course of antibiotics that are suitable for pregnant women most likely, you will get amoxicillin, for three or seven days. Follow the instructions closely and make sure not to miss a dose of antibiotics. You can also work on preventing urinary tract infections by drinking plenty of water, and cranberry juice to cleanse the urinary tract. You can also make sure to pee as soon as you feel the urge (and every pregnant woman knows frequent urination is part of the whole pregnancy deal!) and making sure you get plenty of vitamin C.