S.C.
J. --
Our bodies react to pregnancy in the weirdest ways. When I was pregnant with my daughter, I developed a small but prominent cluster of spider veins next to my nose that grew darker as my pregnancy progressed. As soon as I came home from the hospital after giving birth, the spot had already started fading and was completely gone within two weeks.
If you've had issues with your gums during your pregnancy, then this new development is probably just another manifestation of your galloping hormones. Get it checked out anyway -- you might be able to have it safely treated. But if you're advised to wait, then keep your revulsion in check (easier said than done, I know) and see if it recedes after the baby's born. If it doesn't, get it checked out again.
Congrats on baby #2 and best wishes.