MVVM DataTemplate and ContentPresenter

In my example i have a MainView and in that i want to show a UserControl (ParentView). I'm trying to use MVVM so i also have a MainVM and a ParentVM.

In a resource file i have following code: 

        <DataTemplate x:Key="PVM" DataType="{x:Type local:ParentVM}">
            <local:ParentView />
        </DataTemplate>

The MainVM creates and instance of ParentVM. Instead of adding my ParentView to my MainView in XAML I want to use a ContentPresenter on my MainView. I just can get my ParentView to show up in my MainView when using the ContentPresenter. Can someone help me with this?

Thanks

AHR