Welcome to the forum!
I don't think you mean Excel tables but Excel Ranges as Tables to MSWord. Obviously, autofitting will not be good for large tables.
'Add Table to MSWord
' http://vbaexpress.com/forum/showthread.php?t=23975
' http://vbaexpress.com/forum/showthread.php?p=168731
' Tools > References > Microsoft Word 14.0 Object Library > OK
Sub MacroStudent()
'Step 1: Declare your variables
Dim MyRange As Excel.Range
Dim MyRange1 As Excel.Range
Dim MyCell As Excel.Range
Dim wd As Word.Application
Dim wdDoc As Word.Document
Dim WdRange As Word.Range
Dim wdTable As Word.Table
Dim wdBreak As Word.Break
Dim LastRow As Long
Dim LastColumn As Long
Dim i As Integer
Dim a(1 To 2) As Range
Set a(1) = Range("A6:J11")
Set a(2) = Range("A12:R21")
'Step 3: Open the target Word document
Set wd = New Word.Application
Set wdDoc = wd.Documents.Add 'create a new document
wd.Visible = True
'Step 4: Set focus on the target
Set WdRange = wdDoc.Range
'Step 4.1: Create a blank table in Word
For i = 1 To UBound(a)
a(i).Copy
With wd.Selection
.Paste 'paste in the table
'Step 6: Adjust column widths
.Tables(1).AutoFitBehavior wdAutoFitContent
.EndKey Unit:=wdStory
.TypeParagraph
End With
Next i
'Step 7: Memory cleanup
Application.CutCopyMode = False
Range("A1").Select
Set wd = Nothing
Set wdDoc = Nothing
Set WdRange = Nothing
End Sub