<?php
$args = array(
	'post_type'	=> 'post',
	'post_status'	=> 'publish',
	'meta_key'	=> 'tanggal_lahir', //id
	'orderby'	=> 'meta_value',
	'order'		=> 'DESC',
);
$wp_query = new WP_Query();
$wp_query->query( $args );
if ( $wp_query->have_posts() ) :
	while( $wp_query->have_posts() ) :
		$wp_query->the_post();
     		//Do Something ...
	endwhile;
endif;
?>