Some girls may start menstruating as early as age 10, but others may not get their first period until they are 15 years old. The amount of time between a girl's periods is called her menstrual cycle (the cycle is counted from the start of one period to the start of the next). Some girls will find that their menstrual cycle lasts 28 days, whereas others might have a 24-day cycle, a 30-day cycle, or even longer.
A barium swallow is a special type of X-ray test that helps your doctor take a close look at the back of your mouth and throat, known as the pharynx, and the tube that extends from the back of the tongue down to the stomach, known as the esophagus.
Diagnosing Acid Reflux With a Barium Swallow Radiograph. Your doctor may decide to use a special X-ray procedure -- the barium swallow radiograph -- to rule out any structural problems in your esophagus. In this painless acid reflux test, you will be asked to swallow a solution of barium. The barium enables doctors to take X-rays of your esophagus. Barium swallow isn't a surefire method of diagnosing GERD. Only one out of every three people with GERD has esophageal changes that are visible on X-rays.