Thanks to https://github.com/react-community/react-navigation/issues/271#issuecomment-303217976

example.js

export const UnauthNavigator = StackNavigator({
  Splash: {
    screen: SplashScreen,
    navigationOptions: {
      header: null,
    },
  },
  SignIn: {
    screen: SignInScreen,
    navigationOptions: (props) => ({
      title: 'Đăng nhập',
    }),
  },
}, {
  cardStyle: {
    backgroundColor: '#fff',
  },
  navigationOptions,
  mode: 'modal',
});
navigateOnce(UnauthNavigator);

navigateOnce.js

import {
  NavigationActions,
} from 'react-navigation';

const navigateOnce = (Navigator) => {
  const { getStateForAction } = Navigator.router;
  Navigator.router.getStateForAction = (action, state) => {
    const { type, routeName } = action;
    if (state && state.routes[state.routes.length - 1].routeName == routeName &&
      type === NavigationActions.NAVIGATE) {
      return null;
    }

    return getStateForAction(action, state);
  };
  return Navigator;
};

export default navigateOnce;