Thanks for your replies. I wouldn't use weaning as a way of getting him to sleep more - have kind of got used to 2 hourly feeding sessions at night. I'm going to try to go another month and start him at 5 months I think
DS was 23 weeks. He slept through from 8 weeks, weaning made no difference to this, he was a sleepy baby.
DD was 29 weeks, she was tiny and not ready for weaning until then. She loved it though and she slept through from the night she started having 2 reasonable sized meals a day, at about 7 1/2 months, and I think in her case weaning and sleeping through were related. She was waking purely from hunger, and solid food satisfied her for much longer. DD was eating things like beef stew, fish pie, omelettes, pasta bolognaise, etc. , she didn't sleep though at the start when she was trying out fruit and veg purees, which don't have many calories in them.
Several friends found weaning caused constipation or diahorrea, and that made sleeping worse until it was sorted out!
By solids I mean anything other than breast or formula milk.
DS is 18 weeks. He's 90th percentile for weight and exclusively breastfed. He wakes constantly throughout the night (every 2 hours or so) but then has done for about 8 weeks. He watches is eat very intently and everything he picks up goes into his mouth.
I'm trying to hold off weaning for as long as possible but there is no way I will be able to wait until 6 months. My HV said absolutely do not give him solids before 20 weeks and the later after that the better. He refuses bottles so there is no way I can top him up with formula at the moment.
Also he was 2 weeks late so I wonder if I can add a couple of weeks to his age as far as his digestive system is developed?