Display Activity indicator center

I have below code for display activity indicator. But it's showing top of the screen. I need to display center of the screen.

 IEnumerator Load()
     {
         #if UNITY_IPHONE
             Handheld.SetActivityIndicatorStyle(iOSActivityIndicatorStyle.Gray);
         #elif UNITY_ANDROID
             Handheld.SetActivityIndicatorStyle(AndroidActivityIndicatorStyle.Small);
         #endif
         Handheld.StartActivityIndicator();
         yield return new WaitForSeconds(0);
         Application.LoadLevel("25Nov1");
     }
 
 
 
 if(GUILayout.Button("Start", startbtnstyle)){
             
             StartCoroutine(Load());        
             
             
         }