yes it could be or at least part of the reason

The only way to tell if it's the mattress ...is to replace the mattress. If you still wake up after 4 hrs, it's not the mattress.

I'm begining to believe i have insomnia, and have done a number of things to get myself to sleep faster. sometimes they work other times not. Clearing my mind by concentrating on breathing has helped the most of all. i've started excercizing more, but i do so an hour before bed. (i've read somewhere, i think on a yahoo fitness page, that excercize before bed as long as you have time to wind down won't hamper sleep.) i have trouble doing so in the morning due to fatigue. and midday because i can't properly fit it before my meals, so night time works best. just thought i'd add the info in, maybe someone can point out some help.

You might trying to turn the mattress over that may help, you could also try to not do very much before you go to bed that may keep your brain activity high. Avoid drinking coffee and tea before you try to sleep. Smoking is also a stimulant so it should be avoided as well. Some people find it helps if they have a short walk just before bedtime..

treat yourself to a new matress!

I don't smoke, though my mother does. i very rarely let myself have caffine, sticking with non caffine drinks. i flip the matress often, but that method isn't working very well. what shouldn't i do before bed? seems easier said than done to sit there and do nothing for an hour before bed. i pass the time by turning on a console game system. nothing puzzlelike, hack-and-slash usually. before that i do my night time excersizes. I'll probally just have to get the matress and hope for the best, its gonna frustrate me if i do, and nothing changes lol. Maybe i'm just too picky of a sleeper.. Light sensitive, though i'm currently using a dim light, so i don't break anymore toes. Sound sensitive, but i have to have a white noise, such as my fan. Temperature has to be just right, no warmer than 74 degrees, with the overhead fan breeze. thats using a very light blanket as well. i flip my pillow if it gets warm, and switch from belly to back when body temp becomes a problem. Comfort, i think i have restless leg syndrom too, sometimes i get leg cramps or tingling and need to keep rocking my legs from side to side. restless mind, but i'm getting around to controlling that one, thanks to some meditation article i read somewhere, concentrating on breathing has been the biggest help clear the mind and induce falling asleep. no matter what kind of dreams i have, they tend to wake me up, and i go through phases where i doze off multiple times a night and wake up to a random dream each time. and i absolutely have to use the facility before bed, or that will wake me up.

you can sleep for 4 whole hours without waking up? I average 2. BUT if you're dreaming/remembering your dreams, that's a good sign: you're getting to the deep sleep stages, the restorative stage. deep sleep eluded me till the Dr put me on low-dose Cymbalta. Now, even though I still wake up every 2-3 hours, I get DEEP sleep and remember my dreams now, and it's much more refreshing sleep than before.