maternity prom items for pregnant brides

my daughter is a junior at MJHS. She says the dress code for prom is the same as which they have at school. If that's the case it is nearly impossible to find her a prom dress. she says the principle is against the prom. am I being miss informed or even misled by my daughter about prom? she is a blue jeans and tshirt kinda kid so I wouldn't put it past her to be exaggerating... maternity prom items for pregnant brides