my $pdf = PDF::Create->nw(...);
my $root = $pdf->new_page(...);

# Datenbankzeugs...

my $c = 0;
my $page = $root->new_page();
while(my ($daten) = $sth->fetchrow_array()){
    if($c == 50 or ($c -50) % 60 == 0){
        $page = $root->new_page();
    }
    $page->stringl($daten);
    $c++;
}