diff --git a/packages/babel-helpers/src/helpers.js b/packages/babel-helpers/src/helpers.js
index 8b89f2e55d..682923fea9 100644
--- a/packages/babel-helpers/src/helpers.js
+++ b/packages/babel-helpers/src/helpers.js
@@ -582,17 +582,13 @@ helpers.assertThisInitialized = () => template.program.ast`
 `;
 
 helpers.possibleConstructorReturn = () => template.program.ast`
+  import assertThisInitialized from "assertThisInitialized";
+
   export default function _possibleConstructorReturn(self, call) {
     if (call && (typeof call === "object" || typeof call === "function")) {
       return call;
     }
-    // TODO: Should just be
-    //   import assertThisInitialized from "assertThisInitialized";
-    //   return assertThisInitialized(self);
-    if (self === void 0) {
-      throw new ReferenceError("this hasn't been initialised - super() hasn't been called");
-    }
-    return self;
+    return assertThisInitialized(self);
   }
 `;
 
diff --git a/packages/babel-plugin-proposal-class-properties/test/fixtures/regression/6154/output.js b/packages/babel-plugin-proposal-class-properties/test/fixtures/regression/6154/output.js
index c272ca164b..5561d047d7 100644
--- a/packages/babel-plugin-proposal-class-properties/test/fixtures/regression/6154/output.js
+++ b/packages/babel-plugin-proposal-class-properties/test/fixtures/regression/6154/output.js
@@ -2,7 +2,7 @@ function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterat
 
 function _instanceof(left, right) { if (right != null && typeof Symbol !== "undefined" && right[Symbol.hasInstance]) { return right[Symbol.hasInstance](left); } else { return left instanceof right; } }
 
-function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
 
 function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }
 
diff --git a/packages/babel-plugin-proposal-decorators/test/fixtures/regression/7030/output.js b/packages/babel-plugin-proposal-decorators/test/fixtures/regression/7030/output.js
index b47a62b382..c21f2cdab1 100644
--- a/packages/babel-plugin-proposal-decorators/test/fixtures/regression/7030/output.js
+++ b/packages/babel-plugin-proposal-decorators/test/fixtures/regression/7030/output.js
@@ -4,7 +4,9 @@ function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterat
 
 function _classCallCheck(instance, Constructor) { if (!_instanceof(instance, Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
 
-function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
+
+function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
 
 function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }
 
diff --git a/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/spec/output.js b/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/spec/output.js
index b6a5b878b7..4b7fbb1def 100644
--- a/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/spec/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/extend-builtins/spec/output.js
@@ -1,6 +1,8 @@
 function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
 
-function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
+
+function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
 
 function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }
 
diff --git a/packages/babel-plugin-transform-classes/test/fixtures/regression/T7537/output.js b/packages/babel-plugin-transform-classes/test/fixtures/regression/T7537/output.js
index dc8a3c6389..3b47c5925e 100644
--- a/packages/babel-plugin-transform-classes/test/fixtures/regression/T7537/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/regression/T7537/output.js
@@ -1,6 +1,8 @@
 function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }
 
-function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
+
+function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
 
 function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }
 
diff --git a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super-inline/output.js b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super-inline/output.js
index e019eadfd9..ef3b23c9b2 100644
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super-inline/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super-inline/output.js
@@ -1,6 +1,6 @@
 function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
 
-function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
 
 function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }
 
diff --git a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super/output.js b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super/output.js
index 854033398b..9413bc4a63 100644
--- a/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super/output.js
+++ b/packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-bare-super/output.js
@@ -1,6 +1,6 @@
 function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
 
-function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+function _possibleConstructorReturn(self, call) { if (call && (typeof call === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
 
 function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }
 
diff --git a/packages/babel-plugin-transform-parameters/test/fixtures/regression/6057-expanded/output.js b/packages/babel-plugin-transform-parameters/test/fixtures/regression/6057-expanded/output.js
index c3554cc0ec..e113eb3089 100644
--- a/packages/babel-plugin-transform-parameters/test/fixtures/regression/6057-expanded/output.js
+++ b/packages/babel-plugin-transform-parameters/test/fixtures/regression/6057-expanded/output.js
@@ -19,7 +19,7 @@ function _defineProperties(target, props) { for (var i = 0; i < props.length; i+
 
 function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }
 
-function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
 
 function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }