A crowded bus or train
"For sitting strangers, it is thoughtful, though not mandatory, to offer and give a pregnant woman your seat," says Post. For pregnant women, if no one offers, simply ask someone if he or she would mind giving up a seat.

To ask or not to ask
"Don't be too nosy," Post advises, who recommends avoiding questions about the baby's gender and conception. "It's really important not to get too personal. Take the lead from the expectant mother." In other words, discuss the topics she addresses. If in doubt, don't ask. And questions like, "Is it a planned pregnancy?" and "When are you due?" should never be uttered because you never know if a woman is truly pregnant or, perhaps, has already delivered her baby.

To touch or not to touch
For expecting mothers, field rude questions or the hands-on approach with patience and humor. Post suggests saying "The sleeping baby doesn't want to be touched," "I've been poked or prodded enough," or "I don't like my stomach touched, I'm sure you understand." Be considerate: Don't touch a pregnant woman's stomach or other body parts unless given permission.

A miscarriage
For friends and co-workers, treat it like a death. Don't disregard it, offer advice, or say something as insensitive as, "I'm sure you'll have another." Instead, simply say: "I'm thinking of you. I'm sorry to hear about your loss."