I co-slept with DS1 from about 8mths, before that I'd get up during the night to feed him & find myself falling asleep sitting up - definitely not safe! With DS2 from when we got home, he'd come into our bed from first wake-up & I'm getting so much more sleep this time.

There are safe co-sleeping guidelines - mustn't be affected by drugs, alcohol or exhaustion, must be non-smokers, use blankets rather than doonas (I wear a cardigan to bed to stop me getting too cold)