Blaming God for a miscarriage is way off base.Yet, God destroys a very large percent of those, that naturally miscarry (>30%)
Ergo, doesn't seem that God shares your view here.
You want to blame human imperfection then so be it.
Blaming God for a miscarriage or the death of any child so He can have another angel is a complete disrespect to our Creator. No one values human life more than our creator. Miscarriages and other terrible acts that result in unplanned pregnancies are not on God. It is human choice or human sin and imperfection that is the cause.