Anyhow, I still think this is a very personal question and one that you shouldn't ask. It's not even a question that I'd pose to close friends and relatives because it is such a personal time for the people involved and even if you have your suspicions, you still let them tell you when they are ready to tell you.
Its just one of those questions you don't ask because its rude. The same as if someone wants to brag about how much they earn - fine - let them on, but you don't come out and ask someone how much they earn, or how much they owe on their house or is their child a bit slow, cos you see them doing silly things or is your wife an alcoholic or your husband a gambler. You might be curious about all these things, but to be polite, you just don't ask. You keep schtum!