diff --git a/aider/sendchat.py b/aider/sendchat.py
index e4b8bd7bf..745d10ebb 100644
--- a/aider/sendchat.py
+++ b/aider/sendchat.py
@@ -71,6 +71,8 @@ def simple_send_with_retries(model_name, messages, extra_params=None):
             }
 
             _hash, response = send_completion(**kwargs)
+            if not response or not hasattr(response, 'choices') or not response.choices:
+                return None
             return response.choices[0].message.content
         except litellm_ex.exceptions_tuple() as err:
             ex_info = litellm_ex.get_ex_info(err)
diff --git a/tests/basic/test_sendchat.py b/tests/basic/test_sendchat.py
index a74b2483d..2d953e06d 100644
--- a/tests/basic/test_sendchat.py
+++ b/tests/basic/test_sendchat.py
@@ -85,7 +85,9 @@ class TestSendChat(unittest.TestCase):
         mock.status_code = 400
 
         mock_completion.side_effect = litellm.InvalidRequestError(
-            "Invalid request", response=mock, llm_provider="test_provider", model="test_model"
+            message="Invalid request",
+            llm_provider="test_provider",
+            model="test_model"
         )
 
         result = simple_send_with_retries(self.mock_model, self.mock_messages)