diff --git a/changelog/3143.doc b/changelog/3143.doc
new file mode 100644
index 000000000..b454708ad
--- /dev/null
+++ b/changelog/3143.doc
@@ -0,0 +1 @@
+Added note that calling pytest.main multiple times from the same process is not recommended because of import caching.
\ No newline at end of file
diff --git a/doc/en/usage.rst b/doc/en/usage.rst
index 6091db8be..18830792b 100644
--- a/doc/en/usage.rst
+++ b/doc/en/usage.rst
@@ -387,6 +387,15 @@ hook was invoked::
 
     $ python myinvoke.py
     *** test run reporting finishing
-    
+
+.. note::
+
+    Calling ``pytest.main()`` will result in importing your tests and any modules
+    that they import. Due to the caching mechanism of python's import system,
+    making subsequent calls to ``pytest.main()`` from the same process will not
+    reflect changes to those files between the calls. For this reason, making
+    multiple calls to ``pytest.main()`` from the same process (in order to re-run
+    tests, for example) is not recommended.
+
 
 .. include:: links.inc