You could do like this site does, which is redirect to a separate "success" page, which then uses a meta refresh tag in the <head> section to send you back to the form page:
insert_form.php:
// upon successful completion of the insert:
header('Location: http://www.yoursite.com/insert_success.html');
exit;
insert_success.html:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html lang='en'>
<head>
<meta http-equiv='Content-Type' content='text/html; charset=ISO-8859-1'>
<meta http-equiv="refresh" content="1;url=http://www.charles-reace.com/">
<title>Insert Success</title>
</head>
<body>
<h1>Insert Success</h1>
<p>If you are not automatically returned to the Insert Form, please click the link below.</p>
<p><a href="http://www.yoursite.com/insert_form.php">Insert Form</a></p>
</body>
</html>