diff --git a/Python/pythonrun.c b/Python/pythonrun.c
index 0ae15fa..17d569d 100644
--- a/Python/pythonrun.c
+++ b/Python/pythonrun.c
@@ -242,7 +242,11 @@
 #endif
 
 #ifdef Py_TRACE_REFS
-	if (_Py_AskYesNo("Print left references?")) {
+	if (
+#ifdef MS_WINDOWS /* Only ask on Windows if env var set */
+	    getenv("PYTHONDUMPREFS") &&
+#endif /* MS_WINDOWS */
+	    _Py_AskYesNo("Print left references?")) {
 		_Py_PrintReferences(stderr);
 	}
 #endif /* Py_TRACE_REFS */