When a child is born in Sweden it is the midwife who sends a birth notification to Skatteverket. This happens almost immediately after the child is born and has been checked over by the midwife and doctors.
The new born will receive their personal ID number (personnummer) immediately at birth. Papers and documents requesting forenames and surnames will be sent to the parent’s home in the weeks proceeding the birth.
If the parents are married, this is a very straight forward process. If the parents are co-habiting but not married, it gets a little more complicated. The paternity of the child will requested by the Social Welfare Committee and an application for join custody will be required because custody falls automatically with Mum.
How to apply for join custody in Sweden