I know there are variation from country to country but all the info I can find points to:
* a miscarriage is loss of a baby before 24 weeks
* a still birth is any baby born (vaginal/surgical) dead after 24 weeks
* a pre-mature baby is any baby born alive before 36 weeks
* a term baby is any baby born alive after 36 weeks
so if the young lady in question was past 24 weeks, she suffered a still birth, not a miscarriage.
Either of these is just as devastating as the other.
A still birth does not have to be a baby that died during birth.
If it died during birth, that would have otherwise been a live birth, then the birth still has to be registered.