diff --git a/changelog/10999.bugfix.rst b/changelog/10999.bugfix.rst
index 1eeae02b1..08c68da01 100644
--- a/changelog/10999.bugfix.rst
+++ b/changelog/10999.bugfix.rst
@@ -1 +1 @@
-Fixed bug where monkeypatch setitem/delitem type annotations didn't support typing.TypedDict.
+The `monkeypatch` `setitem`/`delitem` type annotations now allow `TypedDict` arguments.
diff --git a/src/_pytest/monkeypatch.py b/src/_pytest/monkeypatch.py
index 6d63da443..c4a72e49d 100644
--- a/src/_pytest/monkeypatch.py
+++ b/src/_pytest/monkeypatch.py
@@ -295,12 +295,7 @@ class MonkeyPatch:
         self._setitem.append((dic, name, dic.get(name, notset)))
         dic[name] = value
 
-    def delitem(
-        self,
-        dic: Mapping[K, V],
-        name: K,
-        raising: bool = True,
-    ) -> None:
+    def delitem(self, dic: Mapping[K, V], name: K, raising: bool = True) -> None:
         """Delete ``name`` from dict.
 
         Raises ``KeyError`` if it doesn't exist, unless ``raising`` is set to
@@ -341,7 +336,7 @@ class MonkeyPatch:
         Raises ``KeyError`` if it does not exist, unless ``raising`` is set to
         False.
         """
-        environ: Mapping[str, str] = os.environ
+        environ: MutableMapping[str, str] = os.environ
         self.delitem(environ, name, raising=raising)
 
     def syspath_prepend(self, path) -> None: