I just found out I have this from the dentist.

I got a soft toothbrush and Sonicare.

Sonicare keeps you from brushing back and forth which is not good for your teeth/gums.

4month old - I would blame stress.

Kids have destroyed my teeth.

during pregnancy gums tend to be an issue due to hormones. You should go back to normal after delivering. http://www.americanpregnancy.org/pregnancyhealth/swollengums.html

Must see dentist immediately, because roots are much more sensitive (to temperature changes and to cavitities).

Are you flossing? If not, get on that right away.

I wouldn't say to stop drinking soda, but more to make sure you're drinking a large glass of water or two immediately after, to rinse mouth and reduce acidity and increase hydration levels.

As one who has had gum grafts, root canals, and implants, I can only say: get on this immediately.

Sounds like you have gum pockets, rather than simply receding gums. Get thee to a dentist soon! Brushing more softly is not going to take care of your issue.

My dentist told me to always brush in the direction of the gums, so for example, if brushing the top teeth, brush gently downward, so it is like pushing the gums down in the right direction they are supposed to go, lying flush against your teeth. If brushing bottom teeth, brush gently UP. Don't vigorously brush up and down, up and down, up and down. Hope this helps, OP.

Give Up The Soda! Horrible for your teeth, and health in general.

Recessed gums - I have them there too, from brushing too hard. It can make your gums sensitive, too. Mine aren't bad enough for surgery, but I use sensodyne toothpaste (was told not to use whitening) and use a soft toothbrush. I was told to use my non-dominant hand so I don't brush so hard, and also to use an electric toothbrush, if possible.