s is a tricky and by no means comprehensive list of topics. I don't engage in many types of play (blood play particularly comes to mind) so I can only speak to my experiences.
As a switch, most of my fears surrounding pregnancy and BDSM were as a bottom. Thus I spent the first six or so months of pregnancy exclusively topping. If you are a bottom, this may be a good time to play with topping. You feel more in control, you are selecting the toys, and you are the one who is in charge of running the scene. One of the biggest issues I've faced as a pregnant woman is a loss of control of my body...topping was great in that it gave me the illusion of control (and some amount of real control).
However, when you top, you do need to disclose your condition if you're playing with someone who isn't your partner. You need to talk about what limits you might have, such as not using a violet wand on someone (more about electricity play in a minute). You need to explain that your emotional state may cause you to stop a scene, and you'll want to arrange a specific phrase that says you're about to shut a scene down.
Bottoming requires a MUCH more in depth discussion, especially if you're about to submit to someone new. I personally chose to not submit to anyone but Sexyhusband during my pregnancy. It was disappointing at times, and there were people who made it clear that they would enjoy topping me who I would normally have consented to playing with, but the thing is that no one was as invested in the little girl growing inside me as myself and Sexyhusband. Thus, he was the only one I felt comfortable submitting to. Remind yourself that it is OKAY to be uber choosy about who you submit to while pregnant.
You need to talk about your body, and what YOUR limits are as a submissive. You need to go over your body parts like I did in the section above and explain what can and can not be done to your body (depending on what YOU are comfortable with and how knowledgeable the top in question is). You need to have a phrase/safeword that stops the scene cold. Explain your needs regarding aftercare as well.
Don't do it. I'm not kidding. Violet Wands are out. My physical therapist won't even do electro-stim on my back because there's enough of a risk that it could send my uterus into contractions. Everyone is in strict consensus on this one--stay the hell away from electricity play.
Hot Tubs/Hot Water
This is actually in all the pregnancy books. You need to avoid submerging your body in hot water, and raising your internal temperature over 101 degrees maximum. In early pregnancy it can cause death to the fetus, and throughout the pregnancy it can cause harm. Running a fever of 101 or higher is cause to call your OB right away, so hot baths and especially hot tubs are out. It's depressing...believe me, I know, but it's for the little one's safety.
This was the only way that I felt comfortable submitting for quite some time. I invented a pet persona, Kitty, who was a cherished pet kitten of Sexyhusband. I wasn't allowed to be verbal except for meows (which I can do tonally to express a variety of feelings) which made me submissive. There was a cue if I did need to communicate in words, which is a necessity especially when you are pregnant and a position becomes uncomfortable (such as being on all fours, which makes my belly hurt after a while...an increasingly shorter time the heavier my daughter gets). Being a cherished pet keeps you in the submissive role, but doesn't bring any of potential issues that impact play or bondage do.
I found this article on pregnant bondage. It's worth reading in addition to my comments on bondage with regards to specific body parts above. There's also this DVD...not instructional, but if you love bondage and don't want to do it yourself, you can at least watch it being done. I haven't viewed it, but it came up on several google searches. Something worth contemplating, especially in the later stages of pregnancy is that you probably want to avoid doing rope bondage that limits your mobility for one simple reason--the frequent and irresistible need to pee.
Unfortunately, should the baby decide to hang out on your bladder you will go from zero to sixty in very little time. After around 20/24 weeks or so, all the kegeling in the world won't stop you from having an accident. And you probably don't want to cut through expensive pretty fetish rope, do you? Think about doing more decorative bondage as opposed to mobility related bondage.
It bears repeating that you can't be on your back after 16 weeks of pregnancy, even on a soft bed. Do not consent/ask a pregnant woman to lay on her back and get tied down.
I don't know enough about suspension play to give any advice on this topic, but I would guess that it is most likely less safe during pregnancy and you should research it further if you wish to continue to play with suspension.
Like I noted above, you need to take each body part and your/your play partner's competence into account. Make the right judgment calls for you.
I'm basically lumping crosses, spanking benches, etc all into one category. My advice is to be aware of your stomach at all times. I chose not to be tied to a cross when submitting because I found it much safer to brace my body about six inches off the cross so that I kept it safe at all times. You don't ever want to be in a position where a blow would send your stomach into impact with a hard object.
Additionally, remember that after 16 or so weeks you should never be laying on your back. Laying on your back slows blood flow in the vena cava and the aorta which slows blood flow to and from your uterus. This is a rule in general and not just about sex and BDSM.
As I noted above, corsets should be avoided during pregnancy. There are pregnancy corsets, but I don't see the value in spending a ton of money to wear something for such a short period of time. I know it hurts...remember I went to two sex conventions and had to leave my pretty corsets behind...but it's for the best.
As noted above again, heels are to be avoided or worn for short periods of time only.
Tight clothing is going to be problematic, and often painful if it's near your belly. If it doesn't breathe or have give, it shouldn't be near your belly. You can do all sorts of tight things like vinyl/rubber gloves, tops and skirts if you wear them low enough.
You're going to have to get creative because your body is changing and it may not go back to normal. Some women gain a shoe size during pregnancy, so I'd advise against buying cute mistressy boots during pregnancy (or do what I did and go a 1/2 size larger if they are the cutest shoes you've ever seen and you MUST have them). I found that things that were see through and mesh or involved elastic waistbands worked best. Something to consider.