using a nipple shield was an issue for me. I had inverted nipples so at the clinic they introduced me to the nipple shields at the beginning even if at LaLeche meetings they told us to try without them. My babay was really tiny with a tiny mouth so i took the Medela ones the small size. She latched pretty well but the shields were so small that my brest tissue was sqeezing in them so from the beginning (6th day) i had blood and unbelievable pain on my nipples. My ped and lactation consultant was pressing me to wean off but Lydia could not latch at all the areola. So she told me to use the large medela ones. When i used them the baby learned to open the mouth more wide. After that i had mastitis and my ped told me that with a nipple shield the baby doesn't empty the breat well so i started weaning off the breast shields and one day after 1.5 month Lydia latched well without it. It was so wonderful couse i could feel her and it was so much work sterilizing the nipple shield all the time.
Now she 4.5 months and she's latching so well. She eats every 3.5 hours she sleeps 6 hoours at night and during the first 3 meals she doesn't take any bottle with EBM after nursing and i'm so happy.