diff --git a/pandas/core/arrays/period.py b/pandas/core/arrays/period.py
index ab79622ddd8be..d3760abb8eaf3 100644
--- a/pandas/core/arrays/period.py
+++ b/pandas/core/arrays/period.py
@@ -636,6 +636,20 @@ def to_timestamp(self, freq=None, how: str = "start") -> DatetimeArray:
         >>> idx.to_timestamp()
         DatetimeIndex(['2023-01-01', '2023-02-01', '2023-03-01'],
         dtype='datetime64[ns]', freq='MS')
+
+        The frequency will not be inferred if the index contains less than
+        three elements, or if the values of index are not strictly monotonic:
+
+        >>> idx = pd.PeriodIndex(["2023-01", "2023-02"], freq="M")
+        >>> idx.to_timestamp()
+        DatetimeIndex(['2023-01-01', '2023-02-01'], dtype='datetime64[ns]', freq=None)
+
+        >>> idx = pd.PeriodIndex(
+        ...     ["2023-01", "2023-02", "2023-02", "2023-03"], freq="2M"
+        ... )
+        >>> idx.to_timestamp()
+        DatetimeIndex(['2023-01-01', '2023-02-01', '2023-02-01', '2023-03-01'],
+        dtype='datetime64[ns]', freq=None)
         """
         from pandas.core.arrays import DatetimeArray