Calcium oxalate is by far the most common type of kidney stone. Less frequently, uric acid can cause stones. (This is the same chemical compound that is the cause of gout.) Struvite, xanthine, and other types of stones are rare. Some stones are combinations of these minerals and chemicals.
Your doctor will give you a schedule of all the doctor's visits you should have while pregnant. As your pregnancy progresses, you'll see your doctor more often. Most experts suggest you see your doctor: about once each month for the first six months of pregnancy. every two weeks for the seventh and eight month of pregnancy.
Early in your pregnancy, your midwife or doctor will give you written information about how many appointments you're likely to have and when they'll happen. You should have a chance to discuss the schedule with them. If you can't keep an antenatal appointment, let the clinic or midwife know and make another appointment.