diff --git a/lib/pebble.js b/lib/pebble.js
index 3da6ee5c..a6a21859 100644
--- a/lib/pebble.js
+++ b/lib/pebble.js
@@ -49,6 +49,7 @@ function pebble (req, res) {
         }
         if (element) {
             var obj = {};
+            if (!element.sgv) return;
             obj.sgv = scaleBg(element.sgv).toString( );
             obj.bgdelta = (next ? (scaleBg(element.sgv) - scaleBg(next.sgv) ) : 0);
             if (useMetricBg) {