I don't think it is that challenging to compare the cost of an uncomplicated normal spontaneous vaginal delivery in 1963 with an uncomplicated normal spontaneous vaginal delivery in 2015. It would be challenging to compare a normal spontaneous vaginal delivery in 1963 with an octamommy in 2015. But I am not contending that NSVDs were cheaper in 1963 than octamommies are today.
What do you want to compare? All costs of the delivery? Hospital stay for the mom? The child? Just the professional fee for the ob? Are you going to exclude the cost of meds, since there is the potential for a completely different set of meds to be used? Epidurals were rarely used back then. I assume you're going to account for location within the U.S., since charges vary based on that. Are you going to look at the bill, the negotiated charge, the out of pocket costs, or some combination of these amounts?
If this comparison is so easy and important, then I assume it's readily available. If so, could you provide a link as I would be interested to read it.