They told us 5ml every 5-10 mins using a dropper or syringe when we went to the hospital. Thinking about it... they were only happy to discharge DD when she was admitted a couple of weeks ago (dehydration being one of the reasons) when she had 4 wet nappies a day, so keep an eye on output as much as input - especially if you're breastfeeding and don't know how much they're getting.