Depends. Gestational age is usually determined by a combination of calculations based on the last menstrual period, physical examination of the pregnant woman, and fetal ultrasound. There are tests that can be done just before birth to see if the baby's lungs are mature, and after the baby is born a physical examination and scoring system help to determine the degree of prematurity.
Confusing question. It is not clear what tests you are interested in. There are pre-delivery tests to verify how mature a fetus is (how premi) There are dozens of tests that may be involved if a kid is born prematurely.This is not a chat room and your questions are not linked.If you can clarify your area of interest someone can help.