It's common for babies' heads to be a little misshapen, but most of the time this is totally normal. It's usually due to positional plagiocephaly, which happens when a baby's soft spots (the not-fully-hardened bones in their skull that allow babies to squeeze through during delivery), become molded and flattened from spending a lot in the same position, like during sleep.
It's usually not serious and often corrects itself over time. You may be able to speed this process up by alternating which end of the crib you put your baby down to sleep in. Babies tend to look toward the window, door, or whatever is most interesting in the room, so this ensures that she shifts her head equally in both directions and doesn't stay stuck in the same position for long periods. And while it's crucial that your baby sleep on her back (this has been shown to significantly reduce the risk of SIDS, or sudden infant death syndrome), giving her plenty of time on her belly or sitting up supported during the day can help her head shape return to normal.
Your pediatrician will be monitoring your baby's head growth and soft spots during her well-baby visits this year to make sure she's developing normally. If you have any concerns, bring them up at your next appointment.
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