I'm just after some advice if anyone else has suffered from this problem.
I have a 6.5 month old DS and at least 3-4 times a week he's waking up soaked in urine. I have tried using the next sized nappy up but it makes no difference.
I'm up with him now because he woke up as his vest, baby-gro and 2.5tog sleep suit were saturated with urine.
The usual nightly pattern is as follows:
His nappy is put on for bedtime at 7pm and then DS is fed. He is usually asleep for 7.30-8pm. He then usually wakes between 1-2am for a feed. I check his nappy at this point and it is usually slightly damp but certainly not wet as in needing to be changed.
On some occasions I have changed him anyway, even though he really doesn't need it, in order to put a bone dry nappy on him but it leads to a hysterical meltdown in the early hours of the morning and then it takes me ages to get him back to sleep.
After his 1-2am feed he then usually wakes up 3 hours later and is soaked through 
He sleeps on his front, I don't know if that makes a difference or not.
Even when I don't change his damp nappy there's know way that such a small amount of urine already present in the nappy is the reason for such a huge soaking a few hours down the line.
I just don't know what to do to address the problem. I'm sure DS's sleep would be much better if I could prevent this from happening.