At 4 weeks your baby will most likely to in SCN not NICU - all being well. SCN babies are usually in open cots and not requiring assistance with breathing. There are strict rules in SCN as well as NICU.

To enter you need to gown up and remove all jewellery from hands and wrists and scrub up. This is the same for children. (I am discussing tertiary hospitals here not smaller private hospitals that may have different rules - often a little more relaxed due to the lower volume of patient/visit contact). Only allocated visitors can visit your baby and only whilst you are there or the baby's dad is there. Usually only the parents can handle the baby.

If the suck swallow reflex is a little slow as can be the case sometimes - your baby may be tube fed. This is when a tube is inserted into a nostril and this goes into your baby's belly. Your milk will be tubed into this and this is done until that suck swallow reflex is sorted.

As Sherie said some prems can need to be under lights to treat high bilirubin (jaundice).

Fire away with any more questions.