I'm assuming you have a few women in your circle that have had kids and play pretty hard core. I thought I'd offer my 2 cents in the mix since I've been pregnant and have just seen a longtime kinkster friend have a child. Use what works, or not. Just thought I'd offer it up.

My advice to anyone wanting to play while pregnant would be to ask her doctor how strenuous of activity she can participate in. She should likely avoid anything that will raise blood pressure too high, put her in a position where she could fall or land "hard", or do anything that would cause faintness, overheating, or oxygen loss (obviously).  Most women do (or can do) tons of exercise and activity while they are pregnant. The trick is all in pacing.

My friend X got spanked, flogged, caned plenty while pregnant. She usually stayed on a bed or over a very low spanking bench.  Upper body punches/shoulder work/needles probably would be fine too.

No calf or ankle pressure point play as there are points in the lower leg that supposedly could induce contractions.

Nothing near the kidneys (of course).

I have no idea how bondage would or could affect pregnancy issues, but could look really cool if was safe.  Pregnant Karada?  No suspensions, natch. I wouldn't risk that, personally.

Breast play might be hard cause the tissue is so freakin' sensitive. I suppose that all depends on how they play in the first place.  The tissue in the genitals is also extra sensitive, but in a good way, due to the increased volume of blood. Orgasm denial/control might be fun to play with.

If I were playing with a pregnant person, I'd be extremely sensitive to her needs. She'd get serious veto power on things if she felt even the least bit woogy.  I'd make sure the room was cool, there was lots of water and snacks for drops in blood sugar and I'd keep most of the play horizontal to avoid fainting.  Moods can and do change during pregnancy (especially in the first trimester where it's like nausea and PMS times 10) and so the bottoming "mojo" might also change quite a bit, so I'd watch out for that and be ready with lots of aftercare.

The only other thing that might occur for her, and honestly its not anything I could address sufficiently, might be be issues of "now that I'm a mom, is kink/sex/swing wrong to do" stuff.  Our society does place a burden on women with the madonna/whore thing, like once you are a mom you have to get a practical haircut and wear comfortable shoes and not fuck. I did have some odd moments where I felt weird about sex while pregnant. My husband didn't, even though sometimes men react funny too. 



Light bondage--you want to make sure that you aren't cutting off blood
flow and that you aren't stressing any joints (because your body is
producing hormones to relax your joints and you can easily do damage to
yourself). Pretty, decorative bondage isn't a problem though.

*Light* impact is generally considered ok and generally only on the
butt/thighs. Most of the wisdom that I have seen is that you avoid
hitting the torso.

I was pointed at a study (that I can't find right now) that shows that
increased exposure to adrenaline (that fight or flight/fear response)
increases the likelihood that your male offspring will be gay. They've
done some interesting studies about post-war children. Not that I think
this study should one way or another influence anyone :) I don't care
one way or another if my kids end up gay.

Due to finding references to tens units used during labor for pain
relief I tried using a vaginal plug a couple weeks ago with my Erostek,
that was fine. I would be careful about electrical play further up the
abdomen. Though they are recommended on the lower back during labor.
(Note: I am not actually recommending using a tens unit. I am saying I
did it and didn't have a problem. YMMV)

Due to the fact that your breasts are becoming useful for perhaps the
first time in your life (first kid?) you should probably avoid most
impact/stress on your breasts. They are probably sensitive enough right
now that the idea of them being hurt is unpleasant anyway. However, I
handled a few clothespins a couple weeks ago and that was fun. I won't
let anyone hit mine at the moment because cysts are always a possibility
with impact on the breasts and I don't want to mess up milk production.

Be careful of anything like bastinado because there are some labor
induction points on the feet that you really don't want to be messing
with. That's part of the reason that you shouldn't do hard foot massage
during pregnancy. (There are also labor induction points around the
ankles, so bondage around your ankles should be very loose.)

Don't do anything that will reduce your airflow no matter how much you
like it. Right now you *really* need all the oxygen you can get. Hoods
might be enough reduced airflow to cause a problem. This hasn't been
extensively studied because no one wants to be the test case. :(

Along with bondage, be careful what positions you try to hold in general
because your joints and ligaments can be messed up very very easily.
It's really important that you only try to hold positions that are ok
for your body. You can generally feel early on when something is growing
uncomfortable and this is not the time to "tough it out."

Overall the prevailing information I have been given is that you should
listen to your body. The majority of people I have talked to lose almost
all interest in any impact play during the first trimester, but this is
not a set in stone thing. Some people still like it. The first trimester
is when it is easiest to trigger your body to miscarry so even though it
seems counter-intuitive on some level (Hey--I'm not that pregnant yet, I
shouldn't have to change my life much yet) this is actually the time
when you need to exert the most caution. Later in your pregnancy your
body will tell you when to stop and you really need to listen. Don't try
to push through the pain! :)

My interest in bdsm has come and gone in the last 7 months. Or rather,
was gone for a while and has now returned. :) Just be careful and if
something feels bad, don't do it.