diff --git a/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/CHANGELOG.md b/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/CHANGELOG.md
index b44da84baa9e..86b4c17399db 100644
--- a/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/CHANGELOG.md
+++ b/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/CHANGELOG.md
@@ -18,6 +18,11 @@
 the telemetry offline for retrying at a later time.
 ([#38832](https://github.com/Azure/azure-sdk-for-net/pull/38832))
 
+* Fixed an issue where `OriginalFormat` persisted in TraceTelemetry properties
+  with IncludeFormattedMessage enabled in OpenTelemetry LoggerProvider. This fix
+  prevents data duplication in message fields and properties.
+  ([#39308](https://github.com/Azure/azure-sdk-for-net/pull/39308))
+
 ### Other Changes
 
 * Update OpenTelemetry dependencies
diff --git a/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Internals/LogsHelper.cs b/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Internals/LogsHelper.cs
index 9bc8b6fae5f7..e64c3867cd72 100644
--- a/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Internals/LogsHelper.cs
+++ b/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Internals/LogsHelper.cs
@@ -6,6 +6,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Globalization;
+using System.Linq;
 using System.Reflection;
 using System.Text;
 using Azure.Monitor.OpenTelemetry.Exporter.Internals.Diagnostics;
@@ -66,9 +67,27 @@ internal static List<TelemetryItem> OtelToAzureMonitorLogs(Batch<LogRecord> batc
         {
             string? message = logRecord.Exception?.Message ?? logRecord.FormattedMessage;
 
-            if (logRecord.Attributes != null)
+            foreach (KeyValuePair<string, object?> item in logRecord.Attributes ?? Enumerable.Empty<KeyValuePair<string, object?>>())
             {
-                ExtractProperties(ref message, properties, logRecord.Attributes);
+                if (item.Key.Length <= SchemaConstants.KVP_MaxKeyLength && item.Value != null)
+                {
+                    // Note: if Key exceeds MaxLength, the entire KVP will be dropped.
+                    if (item.Key == "{OriginalFormat}")
+                    {
+                        if (logRecord.Exception?.Message != null)
+                        {
+                            properties.Add("OriginalFormat", item.Value.ToString().Truncate(SchemaConstants.KVP_MaxValueLength) ?? "null");
+                        }
+                        else if (message == null)
+                        {
+                            message = item.Value.ToString();
+                        }
+                    }
+                    else
+                    {
+                        properties.Add(item.Key, item.Value.ToString().Truncate(SchemaConstants.KVP_MaxValueLength) ?? "null");
+                    }
+                }
             }
 
             WriteScopeInformation(logRecord, properties);
@@ -192,33 +211,6 @@ internal static SeverityLevel GetSeverityLevel(LogLevel logLevel)
             }
         }
 
-        private static void ExtractProperties(ref string? message, IDictionary<string, string> properties, IReadOnlyCollection<KeyValuePair<string, object?>> stateDictionary)
-        {
-            foreach (KeyValuePair<string, object?> item in stateDictionary)
-            {
-                if (item.Key.Length <= SchemaConstants.KVP_MaxKeyLength && item.Value != null)
-                {
-                    // Note: if Key exceeds MaxLength, the entire KVP will be dropped.
-
-                    if (item.Key == "{OriginalFormat}")
-                    {
-                        if (message == null)
-                        {
-                            message = item.Value.ToString();
-                        }
-                        else
-                        {
-                            properties.Add("OriginalFormat", item.Value.ToString().Truncate(SchemaConstants.KVP_MaxValueLength) ?? "null");
-                        }
-                    }
-                    else
-                    {
-                        properties.Add(item.Key, item.Value.ToString().Truncate(SchemaConstants.KVP_MaxValueLength) ?? "null");
-                    }
-                }
-            }
-        }
-
         private static string ConvertDepthToString(int depth) => $"{depth}";
     }
 }
diff --git a/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/LogsHelperTests.cs b/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/LogsHelperTests.cs
index 99a931fb7507..a781d69873f9 100644
--- a/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/LogsHelperTests.cs
+++ b/sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/LogsHelperTests.cs
@@ -87,13 +87,11 @@ public void MessageIsSetToFormattedMessageWhenIncludeFormattedMessageIsSet()
             var message = LogsHelper.GetMessageAndSetProperties(logRecords[0], properties);
 
             Assert.Equal("Hello from tomato 2.99.", message);
-            Assert.True(properties.TryGetValue("OriginalFormat", out string value));
-            Assert.Equal(log, value);
             Assert.True(properties.TryGetValue("name", out string name));
             Assert.Equal("tomato", name);
             Assert.True(properties.TryGetValue("price", out string price));
             Assert.Equal("2.99", price);
-            Assert.Equal(3, properties.Count);
+            Assert.Equal(2, properties.Count);
         }
 
         [Fact]