diff --git a/src/index.ts b/src/index.ts
index ba89a06..88fcb57 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -40,7 +40,7 @@ class PrometheusMetrics implements Metrics {
       register.clear()
     }
 
-    if (init?.preserveExistingMetrics !== false) {
+    if (init?.collectDefaultMetrics !== false) {
       log('Collecting default metrics')
       collectDefaultMetrics(init?.defaultMetrics)
     }