Programatically adding a user: extended data.

I’m trying to add a user programmatically:

$user_id = wp_insert_user(
    array(
      'user_login'  =>  $email,
      'user_pass' =>  $pass,
      'first_name'  =>  $form->data['first_name'],
      'user_nicename'  =>  $form->data['first_name'],
      'last_name' =>  $form->data['last_name'],
      'user_email'  =>  $email,
      'display_name'  =>  $form->data['first_name'] . ' ' . $form->data['last_name'],
      'nickname'  =>  $form->data['first_name'] . ' ' . $form->data['last_name'],
      'role'    =>  'contributor'
    )
  );
  update_user_meta( $user_id, 'gender', $form->data['gender'] );
  update_user_meta( $user_id, 'date_of_birth', $form->data['date_of_birth'] );
  update_user_meta( $user_id, 'address', $form->data['address'] );
  update_user_meta( $user_id, 'postcode', $form->data['postcode'] );
  update_user_meta( $user_id, 'phone', $form->data['phone'] );
  update_user_meta( $user_id, 'mobile', $form->data['mobile'] );
  update_user_meta( $user_id, 'em_contact_name', $form->data['em_contact_name'] );
  update_user_meta( $user_id, 'em_contact_number', $form->data['em_contact_number'] );
  update_user_meta( $user_id, 'avatar', $form->data['avatar'] );

My user is getting inserted okay, but I’m expecting the additional data to be placed in the ‘users_meta’ table, which it isn’t.

What am I doing wrong?