The most common method of checking the birth control ring is X-ray. This method is simple and easy to implement. The metal ring can be developed under X-ray fluoroscopy. By inspection, it can be observed whether there is a contraceptive ring in the uterine cavity and whether the position of the contraceptive ring in the uterine cavity is normal. X-ray fluoroscopy is not accurate in determining the position of the birth control ring, and the plastic ring is not developed under X-ray fluoroscopy, so the plastic ring in the uterine cavity of the X-ray examination room cannot be used.

      The use of B-mode ultrasound diagnostic apparatus can not only determine whether there is a contraceptive ring in the uterine cavity, but also determine the position, size and shape of the uterus, and then determine the position of the contraceptive ring in the uterine cavity, so it is more accurate than X-ray fluoroscopy Much. In addition, B-mode ultrasound has no side effects of radiation, and both metal and plastic rings can be inspected. Since the B-mode ultrasound diagnostic apparatus has not been popularized in the majority of rural medical units, it is not currently available for general inspection of birth control rings.

      The metal ring can also be detected by a metal alarm. It can only determine whether there is a birth control ring in the uterine cavity, but cannot determine whether the position of the metal ring in the uterine cavity is normal.

      The non-metallic rings are all equipped with nylon tail wires, which leave part of the tail wires outside the cervical opening when placed. To check this kind of birth control ring, you can observe the length of the tail wire from the cervix through the vagina to know whether the birth control ring is properly positioned. If the tail wire is not seen during the inspection, a B-type ultrasound should be used for further inspection to determine whether the contraceptive ring has fallen off or the tail wire is retracted.