diff --git a/javascripts/govuk/analytics/google-analytics-universal-tracker.js b/javascripts/govuk/analytics/google-analytics-universal-tracker.js
index ac18ac90..3a64a2c7 100644
--- a/javascripts/govuk/analytics/google-analytics-universal-tracker.js
+++ b/javascripts/govuk/analytics/google-analytics-universal-tracker.js
@@ -72,11 +72,7 @@
     // Label is optional
     if (typeof options.label === 'string') {
       evt.eventLabel = options.label
-    }
-
-    // Page is optional
-    if (typeof options.page === 'string') {
-      evt.page = options.page
+      delete options.label
     }
 
     // Value is optional, but when used must be an
@@ -85,21 +81,19 @@
     if (options.value || options.value === 0) {
       value = parseInt(options.value, 10)
       if (typeof value === 'number' && !isNaN(value)) {
-        evt.eventValue = value
+        options.eventValue = value
       }
+      delete options.value
     }
 
     // Prevents an event from affecting bounce rate
     // https://developers.google.com/analytics/devguides/collection/analyticsjs/events#implementation
     if (options.nonInteraction) {
-      evt.nonInteraction = 1
+      options.nonInteraction = 1
     }
 
-    // Set the transport method for the event
-    // Typically used for enabling `navigator.sendBeacon` when the page might be unloading
-    // https://developers.google.com/analytics/devguides/collection/analyticsjs/field-reference#transport
-    if (options.transport) {
-      evt.transport = options.transport
+    if (typeof options === 'object') {
+      $.extend(evt, options)
     }
 
     sendToGa('send', evt)
diff --git a/spec/unit/analytics/google-analytics-universal-tracker.spec.js b/spec/unit/analytics/google-analytics-universal-tracker.spec.js
index 7bc4a002..8a6f10a0 100644
--- a/spec/unit/analytics/google-analytics-universal-tracker.spec.js
+++ b/spec/unit/analytics/google-analytics-universal-tracker.spec.js
@@ -100,6 +100,13 @@ describe('GOVUK.GoogleAnalyticsUniversalTracker', function () {
       )
     })
 
+    it('tracks custom dimensions', function() {
+      universal.trackEvent('category', 'action', {dimension29: 'Home'})
+      expect(window.ga.calls.mostRecent().args).toEqual(
+        ['send', {hitType: 'event', eventCategory: 'category', eventAction: 'action', dimension29: 'Home'}]
+      )
+    })
+
     it('the label is optional', function () {
       universal.trackEvent('category', 'action')
       expect(window.ga.calls.mostRecent().args).toEqual(