How does custody work when biological father moves out of state and child is not born yet?

You should file a paternity case to get custody and establish what rights the father will have. It is doubtful that will be able to take the child out of state. Consult with an attorney to discuss your options further.

The biological father has all the rights of any other parent. I am assuming that the conception and your relationship with him was in Michigan, and that he has decided to move. If that is true generally the courts will cause him to bear the majority of the additional costs caused by his volitional move. Regarding custody, it is generally rare for a father to get the custody of an infant immediately following birth. On the other hand, depending on the circumstances, it is certainly possible that he could get custody is the biological father, and if that was established, that might be in a different state. All of the various factors would be taken into consideration as well as your means and ability to travel. I would suggest that you see an attorney regarding establishing the Michigan courts jurisdiction over the unborn child prior to the time that he seeks to have another state's courts gain control.