diff --git a/mongo/session.go b/mongo/session.go
index 22aa026c9e..8f1e029b95 100644
--- a/mongo/session.go
+++ b/mongo/session.go
@@ -233,7 +233,7 @@ func (s *sessionImpl) WithTransaction(ctx context.Context, fn func(ctx SessionCo
 
 	CommitLoop:
 		for {
-			err = s.CommitTransaction(ctx)
+			err = s.CommitTransaction(newBackgroundContext(ctx))
 			// End when error is nil, as transaction has been committed.
 			if err == nil {
 				return res, nil