There is a whole list of things you should never ask, even close friends.
- Was it planned?
- Are you pregnant?
- When are you having kids?
- Are you having more?
- Are you done?
Here are versions you can safely ask or say.
- Are you excited? What great news! Congratulations!
- You look GREAT! (Never ever comment that someone looks pregnant or on how big they are if you know they are pregnant. Some do not mind, some are very hurt) And if they are pregnant and not yet sharing, there is a reason. Respect that. If they want to tell you, they will, when they are ready.
- How have you been lately? (Do not ask people if they intend to have kids. If you know them well, eventually they will say it if they do. You can feel free to talk about wanting, or not wanting, kids yourself though).
- How is your child(ren)? You can ask how someone's kids are doing. Don't ask if they are having more. Maybe they are, maybe they won't. Maybe they want to but their partner doesn't & it's a hard topic. Either way, it really doesn't matter. If & when they do have more, I am sure they will let you know, until then, it really doesn't matter anyway.
- This is same as above.
Really, saying you are close to a person in no way means you can cross over boundaries that are reasonable. Asking someone about their reproduction is really overly personal even for siblings and parents for many. Asking questions that literally pertain to someone's sex life needs to be taken as asking about their sex life.
Here is a perfect example. If a close friend is pregnant & asks me about healing after birth as it relates to your sex life, then that I understand. She is asking me to inform her of something that does or will directly impact her. She may also ask after the baby about how to feel sexy again, how do mom's find time, etc and again, also makes sense, she is seeking information as it pertains to an issue she is having. Randomly asking me about my sex life with my spouse because she is curious, even if a close friend, is overstepping. People still do that, but it's rude and not something you should seek to do.
If you are good friends and the couple didn't plan on this, eventually likely the friend will say so. In the end though, planned or not makes no difference as the baby is on the way, so focus on that. If you are a good friend you can ask if there is any way you can help or something you might do, such as help set up a baby crib or paint a room or move furniture or whatever.