The reason that your Prenatals were brand, is that ALL the generics were recalled. Made by KV manufacturer who got into trouble with the FDA for failing some standards.

The only difference with RX and OTC is the folic acid content.
You can buy OTC and add your own folate to make 1mg.
Annie is right...iherb.com is wonderful.

In fact there is one that is "almost" the same as RX prenatals.
http://www.iherb.com/ProductDetails.aspx?pid=759&at=0
800mcg of folic acid is 80% of the RX brands.
240 days' supply for $18.88... good price!
NOW brand is a good company too!

If you are having gum problems, taking extra C and CoQ-10 may help. CoQ10 improves gum circulation. You'd need at least 100mg a day for that. (choose a form that is a gel cap with Q sorb or other enhancing absorption type)