The first thing for you to learn on this particular topic is that most of the time you should follow the advice of your doctor. In fact, almost all of the time you should do this. This article is not presented as a replacement for your doctor’s advice, but rather as a way to teach you some of the thinking involved in medical testing so that you understand better why your doctor might be advising you to do such a thing. From that point of view, it is important to understand that administering medical tests is always going to be a balance between the needs of the patient and the cost involved in administering the test. That is the unfortunate reality of the modern world and nothing is really going to change that anytime soon.
Even if you happen to be insured, most of the insurers are going to be very reluctant to spring for the full package of medical tests that are available. Your doctors understand this and as a result are going to make recommendations based on the number of tests that are financially feasible cross-referenced with what they know about you and your medical history. The only test that basically gets administered to everyone is the ultrasound, which is done right at the start of the pregnancy to make sure that everything is okay.
Beyond the ultrasound, every test is going to be evaluated by the doctor and they will then make a determination as to whether a particular test is deemed medically necessary. There are some tests that patients might want, but which are not really necessary to get. A good example of this would be the cystic fibrosis screening test. Cystic fibrosis is definitely a terrifying disease to most of the people in general society, but the fact of the matter is that there is usually nothing to be worried about if there is no family history of cystic fibrosis present. This is why a doctor might recommend that you avoid taking the test, especially when you also consider that it is one of the more expensive tests out there relatively speaking.