Checkbox databinding default value null

I am databinding a checkbox to a bindingsource, if i dont click the checkbox it will return a null value to my database.

This is the databinding code:

 checkGehuwd.DataBindings.Add("Checked", PersonenBindingSource, "gehuwd", true,
            DataSourceUpdateMode.OnPropertyChanged);

how do i return a default value of false?

Greetings Andy