We're thiiiiinking about trying for child #3; it's an open question,
given our respective ages, whether this will even be a possibility.
Lately I've read about women going to the dentist, the OB, the PCP et
al prior to trying to become pregnant, just wanting to be 'checked.'
Is this overkill? (I admit, sounds like overkill to me.) Did anyone
*do* this, and if so, for what reasons?

it doesn't sound unreasonable, though if you're up to date probably not
necessary, so if you haven't been to the dentist in 5 years, might be
better to go than find you have a problem during pregnancy and not
necessarily having all options open to sort it out. Getting immunities
checked might also be reasonable, particularly if there's been a
moderate gap since a previous pregnancy when they probably will have
been checked. Same goes for you annual, if you had it a month ago, no
need to go again, you don't want to end up going a long time between
them simply due to pregnancy and breastfeeding (if you're happy with
3yrly screening as is common in many other countries then it's not
really an issue). Check meds if you are on any. If you've had GD in a
previous pregnancy, or are obese, or have other risk factors for type 2
diabetes, as an older mother a screening check might well be a
reasonable idea, out of control blood sugars are not great for a
developing foetus.

Other things to think about might be, are you exercising, if so, do you
know if there are any changes you have to make if you get pregnant etc.
What about diet, are you eating a balanced diet, what will you have to
stop eating, does that make you deficient in anything. Check the label
of your vitamins if you take them to see if there is enough folic acid,
if there isn't or you don't take them, then make other arrangements.

Good Luck

Anne