For something like your specific example where it appears that you have running text this "MIGHT" work fundamentally. The document needs to be in print layout view. Basically, it loops through the Page, Rectangle and Line objects and sees "." " " and "This" as the Previous.Previous, Previous and Last word of the line. In that condition, the Previoius word (or the space between the "." and This) is replaced with a line break forcing "This" to the next line."
Code:
Sub LoopByLine()
Dim oPage As Page
Dim lngRec As Long, lngLine As Long
Dim oRng As Word.Range
For Each oPage In ActiveDocument.ActiveWindow.ActivePane.Pages
For lngRec = 1 To oPage.Rectangles.Count
For lngLine = 1 To oPage.Rectangles(lngRec).Lines.Count
Set oRng = oPage.Rectangles(lngRec).Lines(lngLine).Range
If oRng.Words.Last.Previous.Previous = "." Then
oRng.Words.Last.Previous = Chr(11)
End If
Application.ScreenRefresh
Next lngLine
Next lngRec
Next oPage
lbl_Exit:
Exit Sub
End Sub
However, in practice and considering that the result you see on your PC could be vastly different than what I would see on my PC, it is probably a futile exercise. Whatever you do, save and publish as a PDF file before distribution.