answered about 15 months ago by grubby
To me it seems like every third shop is selling maternity clothes (vai bau), but there are especially heavy concentrations of shops on Ba Trieu and Pham Ngoc Thach, it seems.
The one my wife liked on Ba Trieu was a few blocks before Vincom, on the left. Sorry - should have got the address and posted it on the site.
Also, congratulations!