I am 30 weeks pregnant with DC3 and am suffering from hellishly bad leg cramps in the middle of the night - mostly in my calves but also thighs and knees. I had cramps when I was pregnant with DS2 but nothing like as bad as now. The pain is worse than being in labour. The midwife suggested drinking tonic water which I tried but it didn't seem to have any particular effect. Any tips from wise mumsnetters appreciated....