And here's my disclaimer: I'm not saying go ahead and get pregnant. HSP can appear and act differently in different people, and what I experienced may not be the same for someone else. So talk to you doctor about whether or not it might be right for you.
Before I became pregnant, I was told that I would likely have to be in a wheelchair by the end of the pregnancy. I was happy to do whatever was needed, but I didn't particularly want to have to move to a wheelchair. So obviously, my main concern was how would my already weak legs and poor balance hold up to a major change in my weight. I was extremely fortunate, and really it wasn't too bad. I gained about 40 pounds by then end, which is a bit high, but I was considered 'underweight' before I became pregnant so it's actually not that much. I really didn't find I had much trouble with the extra weight until later in my third trimester. I found I had a lot harder time getting up out of chairs, and especially up off of the ground. But as far as balance went for walking, if I had my cane I was pretty much the same as before. I did try to be extra careful though, because I really didn't want to have a bad fall.
The really amazing thing though, was that I found my legs actually seemed to work better. I often have 'bad' and 'good' leg days, where my legs sometimes feel like they will barely move, and others where everything isn't so bad. But during my pregnancy, I very rarely had 'bad' leg days. I really can't explain what happened, but for some reason walking was just a little bit easier. I remember my husband making comments several times about how I was walking so well, and he even noticed that I wasn't having many 'bad' days. That is pretty good considering I expected things to be worse. My guess is that perhaps the relaxin hormone, which is much higher during pregnancy, actually relaxed my leg muscles, reducing the stiffness. But I really don't know. It was a bit of a miracle though, that when I really really needed it, my legs were just a tad better for me.
Another thing I had to consider during pregnancy was what medicines and supplements to take. I decided to stop taking all of my HSP related things, because so little research has been done with them that I just figured it wasn't worth it, even though the suspected risk is extremely low. So, that meant stopping Baclofen. I had been on a pretty low dose, so I didn't find too much of an effect coming off of it. I also took extra supplements - normally my doctor recommends pregnant women take 1 mg of folic acid, but she suggested I take 4 mg because of my HSP.
Overall, I was really blessed throughout the pregnancy. I can't believe how well it went. I was seen at a high risk pregnancy clinic in a city about an hour away, but because everything went just fine, they have recommended that next time I can go to a normal clinic in my town. So, while HSP does add some extra difficulties to pregnancy, it is certainly manageable. And now it's all over and I have the perfect little boy - absolutely worth it!