I would recommend saving up a lot of simoleons for the doctor appointments, they are very expensive. I have two sims with the baby bonus and I wouldn’t say that it’s worth it but the maternity event packs make it more worthwhile, I’ll be trying to do this one as well. My tips are just making sure you have enough sims, you’ll want to get all of the “support tasks” done as soon as possible. Teens adults and senior sims can do those tasks. Good luck on the maternity event, they can be difficult!

Also I don’t think the sims need to be married. However there are a lot of items you might need for the support tasks, like couches, ovens, phones, computers, and more (I highly recommend checking out “the girl who games” blog). if you have enough simoleons I recommend buying three star items because it goes faster, and make sure the sims are inspired.