diff --git a/potx.inc b/potx.inc
index 8490b43..f470777 100644
--- a/potx.inc
+++ b/potx.inc
@@ -630,8 +630,7 @@ function _potx_translation_export($translation_export_langcode, $string, $plural
       $query->condition('t.' . $language_column, $translation_export_langcode);
 
       if ($number_of_plurals > 1) {
-        $string = implode(PoItem::DELIMITER, $strings);
-        $query->condition('s.source', $string);
+        $query->condition('s.source', implode(PoItem::DELIMITER, [$string, $plural]));
         $result = $query->execute();
         if ($result && $translations = $result->fetchField()) {
           $translations = explode(PoItem::DELIMITER, $translations);