diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5d78a36367ca..7f9e48beb9dd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+## 5.12.3
+
+- [apm] fix: Remove undefined keys from trace.context
+
 ## 5.12.2
 
 - [apm] ref: Check if Tracing integration is enabled before dropping transaction
diff --git a/packages/apm/src/span.ts b/packages/apm/src/span.ts
index 2ea97b86ed4d..d1a6c1203aec 100644
--- a/packages/apm/src/span.ts
+++ b/packages/apm/src/span.ts
@@ -314,35 +314,43 @@ export class Span implements SpanInterface, SpanContext {
    * @inheritDoc
    */
   public getTraceContext(): object {
-    return {
-      data: this.data,
-      description: this.description,
-      op: this.op,
-      parent_span_id: this._parentSpanId,
-      span_id: this._spanId,
-      // Undefined status will be dropped by `JSON.stringify` anyway so it's safe to read it directly like that
-      status: this.tags.status,
-      tags: this.tags,
-      trace_id: this._traceId,
-    };
+    // JSON.parse + JSON.stringify to remove undefined values
+    // tslint:disable-next-line: no-unsafe-any
+    return JSON.parse(
+      JSON.stringify({
+        data: this.data,
+        description: this.description,
+        op: this.op,
+        parent_span_id: this._parentSpanId,
+        span_id: this._spanId,
+        // Undefined status will be dropped by `JSON.stringify` anyway so it's safe to read it directly like that
+        status: this.tags.status,
+        tags: this.tags,
+        trace_id: this._traceId,
+      }),
+    );
   }
 
   /**
    * @inheritDoc
    */
   public toJSON(): object {
-    return {
-      data: this.data,
-      description: this.description,
-      op: this.op,
-      parent_span_id: this._parentSpanId,
-      sampled: this.sampled,
-      span_id: this._spanId,
-      start_timestamp: this.startTimestamp,
-      tags: this.tags,
-      timestamp: this.timestamp,
-      trace_id: this._traceId,
-      transaction: this.transaction,
-    };
+    // JSON.parse + JSON.stringify to remove undefined values
+    // tslint:disable-next-line: no-unsafe-any
+    return JSON.parse(
+      JSON.stringify({
+        data: this.data,
+        description: this.description,
+        op: this.op,
+        parent_span_id: this._parentSpanId,
+        sampled: this.sampled,
+        span_id: this._spanId,
+        start_timestamp: this.startTimestamp,
+        tags: this.tags,
+        timestamp: this.timestamp,
+        trace_id: this._traceId,
+        transaction: this.transaction,
+      }),
+    );
   }
 }