diff --git a/prometheus_client/exposition.py b/prometheus_client/exposition.py
index cbdbb379..281fb1ea 100644
--- a/prometheus_client/exposition.py
+++ b/prometheus_client/exposition.py
@@ -822,9 +822,11 @@ def _escape_grouping_key(k, v):
     if v == "":
         # Per https://github.com/prometheus/pushgateway/pull/346.
         return k + "@base64", "="
-    elif '/' in v or ' ' in v:
+    elif '/' in v or ' ' in v or v in ('.', '..'):
         # Added in Pushgateway 0.9.0.
-        # Use base64 encoding for values containing slashes or spaces
+        # Use base64 encoding for values containing slashes or spaces, and
+        # for "." and "..", which would otherwise be removed from the URL
+        # path as dot segments (the Pushgateway answers with a redirect).
         return k + "@base64", base64.urlsafe_b64encode(v.encode("utf-8")).decode("utf-8")
     else:
         return k, quote_plus(v)
diff --git a/tests/test_exposition.py b/tests/test_exposition.py
index b1acca44..c0fbde24 100644
--- a/tests/test_exposition.py
+++ b/tests/test_exposition.py
@@ -317,6 +317,17 @@ def test_push_with_complex_groupingkey(self):
         self.assertEqual(self.requests[0][0].headers.get('content-type'), CONTENT_TYPE_PLAIN_0_0_4)
         self.assertEqual(self.requests[0][1], b'# HELP g help\n# TYPE g gauge\ng 0.0\n')
 
+    def test_push_with_groupingkey_dot_segments(self):
+        push_to_gateway(self.address, "my_job", self.registry, {'a': '.', 'b': '..'})
+        self.assertEqual(self.requests[0][0].command, 'PUT')
+        self.assertEqual(self.requests[0][0].path, '/metrics/job/my_job/a@base64/Lg==/b@base64/Li4=')
+        self.assertEqual(self.requests[0][1], b'# HELP g help\n# TYPE g gauge\ng 0.0\n')
+
+    def test_push_with_dot_segment_job(self):
+        push_to_gateway(self.address, "..", self.registry)
+        self.assertEqual(self.requests[0][0].command, 'PUT')
+        self.assertEqual(self.requests[0][0].path, '/metrics/job@base64/Li4=')
+
     def test_push_with_complex_job(self):
         push_to_gateway(self.address, "my/job", self.registry)
         self.assertEqual(self.requests[0][0].command, 'PUT')