I have a premie she couldn't latch so the hospital provided me with a nipple shield which was too big for her little mout and everytime I would try to breastfeed she would sound as if she was chocking. So I was provided with a breast pump and would pump into a bottle for her they also told me to supplement her with Enfamil high calorie milk until she gets to at least 5 or 6 lbs she usually drink two ounces of breast milk and after burping her and if she still act like she is hungry I would feed her the high calorie formula or give it to her the next feeding

I have a preemie myself, I just got up to pump. basically just drink plenty of water, and pump every 3 hours. I know it's a lot. but it's been helping me get more milk for my baby.