It is a menopause issue, but can be caused by certain illnesses as well. Even people going through chemo can get night sweats.
I only have a mild case and get wet around my chest area, then I wake up cold and uncomfortable. I had (and sold) an online store that sold wicking sleepwear, and it really works. The sleepwear is made of a fabric that wicks the moisture away from your body and it evaporates, keeping you dry so you can sleep.
If you only have the sweats occasionally, you'd have to wear the jammies all the time just in case. I know there's another BWS member that sells these jammies - here's a link to her store:http://www.lunarradiance.com/?gclid=CKHg57iJuJ4CFShGagodAgtOmg
If you decide to purchase some, keep in mind that you don't want a skimpy set. You need to buy sleepwear that touches the parts of your body that sweat, so they can do their job. There are also sheets available as well; they are very expensive but are cool and crisp and really work wonders.