So some ways to stay asleep longer include practicing good sleep hygiene, which includes keeping a cool, dark environment, taking a warm bath at night, and diminishing light exposure in your bedroom, because that will help with the secretion of your melatonin. Melatonin is a hormone that helps with sleep onset.
Now, other ways to help you stay asleep include avoidance of caffeine. Caffeine is a substance that will fight a chemical called adenosine, which helps with sleep onset and getting deeper stages of sleep at night. Avoidance of alcohol can also help you stay asleep a little longer. Now, many people drink alcohol to help them fall asleep, but what they don't realize is that in the second half of the night, you might be getting fragmented sleep after you've metabolized all that alcohol. So avoidance of that will help you stay asleep longer and get a better quality sleep.
You also want to take better control of medical disorders that might be contributing to fragmented sleep. Some of these disorders include benign prostatic hypertrophy, which will cause an increase of urination at night. Same for diabetes, which will also cause an increase in urination at night.
You also want to take better control of pain syndromes that you might have, such as arthritis. You also want to be evaluated for any primary sleep disorders that could be contributing to poor sleep at night and this includes sleep apnea, periodic limb movements, or restless legs.
So a thorough evaluation and history is needed by your physician to see if you just need to be practicing good sleep hygiene, or there's something more that might be contributing to sleep fragmentation at night.