After setting aside for delivery fee and baby room/car seat/stroller/clothes budget, we add baby cost for at least a few months. Then we just need to keep saving regularly. I look at baby cost from other articles and budget it.
It's important to prepare for the cost of having a baby. I suggest you can buy a pregnancy insurance. Here are the best ones in Singapore. https://sg.theasianparent.com/pregnancy-insurance-singapore
We go with the flow. Our child CDA always top up for back up for education, medicine, doctor fee, hospitals, check up. We do keep some savings too as a back up in case our child CDA cant be use.