At what point in a pregnancy will you start to get swollen gums?

Hopfully never.: If you don't have anything irritating the gums, they normally wont swell up. An abnormal swelling of your gums while you are pregnant is an over reaction of your body to an irritant, mainly dental plaque. If you brush and floss well through out the pregnancy, you should not have any swelling. If there is an irritant then around the end of the first trimester is when it begins.

Pregnancy Ginivitis: A common gum condition that start normally between the second to eighth month of pregnancy in response to the surge in hormones. It is estimated that nearly 60% of women will develop gingivitis during their pregnancy. Practice good oral hygiene habits to minimize the effects. See your dentist regularly during pregnancy and especially if it becomes severe.