diff --git a/ommongo/session.py b/ommongo/session.py
index 95be5f9..7f24de5 100644
--- a/ommongo/session.py
+++ b/ommongo/session.py
@@ -287,7 +287,7 @@ def execute_query(self, query, session):
 			cursor.sort([('__index_score', {'$meta': 'textScore'})])
 		elif query._rawquery:
 			if query._query_type=='aggregate':
-				cursor = collection.aggregate(query.query, **kwargs)
+				cursor = list(collection.aggregate(query.query, **kwargs))
 			elif query._query_type=='map_reduce':
 				cursor = collection.map_reduce( query._mapreduce_mapper, query._mapreduce_reducer, query._mapreduce_key, query=query._mapreduce_query)
 		else: