Hi SharonL, I had the same problem w my #1 last time, he had difficulty latching on coz my left nip was flat, had to 'rub' & shape it for him each time. I exclusively pumped for 1 month until he was a bit bigger and he learnt to open his mouth wider before I could successfully latch him later on. Some mummies I know pumped exclusively and never once ever latch on their babies ever and could still successfully breastfeed their babies this way for 1.5years so long as u donrt miss the 3hourly pumping time. So gotto be very disciplined and can't be lazy.
The diff mainly is if bb latch on, bb can clear the, milk fm the breast more efficiently and the saliva triggers our uterus to contract. I'm not sure pumping has this effect, but I guess so long as evey 3 hour u pump ,most of the milk is drawn out, the last 20% is still stuck at the back of the breast unless bb latch on, but it's still ok, the breast w still reproduce.
As for medela pure LAN, no need to wash off. I always have it on so no sore nips. Don't wash your nips w water thinking that w be clean for bb when bb suckle coz washing w dry the nip skin. When bb latch on, and if latch wrongly ( eg small mouth can't cover the aerola but only grab the nip) , then likely w tear. I ever lose skin,lose flesh, lose blood before, so very painful. If there is blood in milk, no need to throw, a little bit, they can digest.