What do you say when someone tells you that they're pregnant? There is really only one answer: congratulations. Even if you don't mean it, that is the only proper and logical response.
Pregnancy is a big f*cking deal. Whether or not it was intentional or an accident, you feign excitement because the pregnant person is either a) ecstatic or b) nervous as hell. Your horrible response will only make them more nervous, or cause them to second guess themselves.
So what shouldn't you say when someone tells you they're pregnant? Don't start with questions like “who is the father” or “how did this happen?” Avoid things like “have you thought about the alternative” or “but you're so young.” Just show your f*cking support, cause if they told you, chances are they care what you think.
Just don't be a rude a-hole like the following 27 people. Repeat that fateful word a couple times to yourself: CONGRATULATIONS.