diff --git a/dspace-api/src/main/java/org/dspace/importer/external/metadatamapping/contributor/CombinedMetadatumContributor.java b/dspace-api/src/main/java/org/dspace/importer/external/metadatamapping/contributor/CombinedMetadatumContributor.java
index 0dfa5c05e2f..564ace9418e 100644
--- a/dspace-api/src/main/java/org/dspace/importer/external/metadatamapping/contributor/CombinedMetadatumContributor.java
+++ b/dspace-api/src/main/java/org/dspace/importer/external/metadatamapping/contributor/CombinedMetadatumContributor.java
@@ -78,20 +78,30 @@ public Collection<MetadatumDTO> contributeMetadata(T t) {
 
         for (MetadataContributor metadatumContributor : metadatumContributors) {
             LinkedList<MetadatumDTO> metadatums = new LinkedList<>(metadatumContributor.contributeMetadata(t));
-            metadatumLists.add(metadatums);
+            if (!metadatums.isEmpty()) {
+                metadatumLists.add(metadatums);
+            }
+        }
+
+        if (metadatumLists.isEmpty()) {
+            return values;
         }
 
-        for (int i = 0; i < metadatumLists.getFirst().size(); i++) {
+        int maxSize = metadatumLists.stream().mapToInt(List::size).max().orElse(0);
 
+        for (int i = 0; i < maxSize; i++) {
             StringBuilder value = new StringBuilder();
 
-            for (LinkedList<MetadatumDTO> metadatums : metadatumLists) {
-                value.append(metadatums.get(i).getValue());
+            for (List<MetadatumDTO> metadatums : metadatumLists) {
+                if (i < metadatums.size()) {
+                    value.append(metadatums.get(i).getValue());
+                }
 
-                if (!metadatums.equals(metadatumLists.getLast())) {
+                if (!metadatums.equals(metadatumLists.get(metadatumLists.size() - 1))) {
                     value.append(separator);
                 }
             }
+
             values.add(metadataFieldMapping.toDCValue(field, value.toString()));
         }