I'm not going to use one in my crib. With all of the new research done on SIDS I really don't want to risk it. It's much more likely the baby will be smothered by a bumper than be seriously injured smacking his or her head on the rails of the crib.
I did not use them with my dd. When I had my son, I used them once he could roll and lift his own head(around 3-4months). He is 19 months now, and I still have them. Some people like them, and some don't.
I'm using ours until I lower her crib a notch. To me she's so close to the top it's like a basinette or moses basket. We also have a baby monitor that does the movement/breathing, so if anything were to go wrong we'd know.
I never used them with my first daughter but the crib set I bought for this baby has bumper pads in them. This baby like my daughter will be in my room for the first 3 months, so I might use them after that, or just use them to make the crib look pretty when my baby is not in them. I do know they make breathable bumper pads which I looked into with my daughter.
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