How effective is the shot at preventing pregnancy?

<p>As long as you get your shots on time, this method is very effective. With perfect use the shot is more than 99% effective; with typical use, the it&rsquo;s closer to 94%. </p> <p>In other words: </p> <p>Of those women who use the shot exactly as directed, fewer than 1 in 100 will experience an accidental pregnancy during the first year of using this method. </p> <p>Of those women who do not use the shot exactly as directed, fewer than 6 in 100 will experience an accidental pregnancy during the first year of using this method. </p>