- preg_match: documentation ( source)
<?php
$addr = "http://www.example.com/?pk_lol=VAgin&utm_campaign=printemps&utm_medium=e-mail&utm_source=newsletter1&utm_content=lien-en-haut";
$pattern ="/(utm_campaign=.[^&]+)?(utm_medium=.[^&]+)?(utm_source=.[^&]+)/i";
preg_match($pattern, $addr, $result);
echo ">> ".$result[1]."\n";
echo $addr;