Scenario: You see an obviously pregnant woman. Great, a topic of conversation as ubiquitous as the weather! You have so many questions, and settle on, "When are you due?" Your friend responds, but now you're not sure what to say.
No fear, I'm here to help!
First, assess the situation. Are you a small child? Or, is the person your best friend since childhood, sister, daughter, aunt, or mother? You may be able to get away with any of the following responses. But she might poison your food if you go with the last set. I've warned you, and I wash my hands of your consequences. If the woman is a stranger or acquaintance, stick with the first suggestions. Please.
Second, you probably know already that women's bodies are different. Some women, it seems, barely look like they're expecting until they're on their way to the hospital to give birth. Others know they're pregnant before they even take the test because they look, well, pregnant. A woman on her fifth pregnancy, say, who is 5' 2" with diastasis recti, may appear quite round relatively early. Anyway, here you go. You're welcome.
Good: "Wow, that's great!" Or, "What a great time of year to have a baby!" Or, "You look amazing!"
Neutral: "Hey, that's my brother's birthday." Or, "Well, congratulations!" Or, "Do you always carry out front like that?"
Just Don't: "Oh really? Are you having twins?" Or, "Man, I thought you were due any day!" Or, "Geez, what is your doctor telling you? Are you really going to make it that long?" Or, "I'm actually shocked. You are huge."
And here's a bonus tip: It's definitely best to ask up front about the due date. Because when you start with, "You look like you're ready to pop any day!" and she responds with, "Um, yeah, any day five months from now," you're both going to just feel awkward.