Maybe sub-surface ones.
so I would think that in most cases, they would make arrangements to replace a pregnant women during one of their stops several weeks before her due date.
Wow, you are an idiot! Maybe they could dump everything from a helicopter and 'turn it into a flying gas can' and send it to the sub and hoist the pregnant sailor out just like they sorta did in Hunt for Red October
That's the ticket. Especially since subs don't have anything else to do during their deployments except for liberty port visits. Sure you don't work with Obama, you sure have the insight for it!
From a pregnancy standpoint, I would think one of the issues would be the inability of nuclear trained persons to perform their job.
Certain watchstanders and jobs inherently receive higher radiation exposure than others. For instance, an Engineering Laboratory Technician (ELT) samples the reactor coolant and receives a measurable amount of exposure during this evolution. Likewise, machinist mates in the aux 2 lower level receive more radiation exposure. The regulatory limit for declared pregnant women is 500 mrem during pregnancy which would rarely be a problem, however. There is a desire to keep the radiation exposure as low as possible so I could see Engineers/COs re-assigning work to lower the radiation exposure (and this would possibly have an effect on moprale). Additionally, there is a regulatory requirement to keep the dose as uniform as possible so certian high dose jobs would likely not be possible. These are generally related to maintenance in the reactor compartment when the reactor is shutdown.
I was on a sub and thus did not have much interaction with Navy women during my time on active duty. I will say that the women I saw on tug boats as linehandlers were generally a waste of a crewman. They were not strong enough to handle the lines and had to be assisted by the male linehandlers.