When my wife was pregnant this last summer, we made several trips to Maternity and Beyond as she got bigger and bigger. They had a great selection that made her feel beautiful even on the days when she wasn't sure if she really was (which she was of course!) They have a wide selection of clothes that fit at every trimester as well as some clothing that didn't look to "maternity" that she wore after the baby was born. You can also find nursing bras and such here if you are going to breastfeed.
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