Osteopenia
Osteopenia is the term for the stage before osteoporosis. When you have osteopenia, your bone density has decreased enough that a bone density scan will identify it as an issue, but not severe enough to be a full osteoporosis diagnosis. If you discover that you have osteopenia, there is a much higher chance that you will be diagnosed with osteoporosis in the future, but this is not certain.
There are steps that you can take to maintain healthy bones, such as regular exercise, a healthy diet, maximizing vitamin D intake, quitting smoking, and reducing alcohol intake. There are also some bone-strengthening treatments that may be made available to you.