I rode through both of my pregnancies. I rode all of my horses (greenies on up) for the first 6 or 7 months, and then handed my youngsters over to a kid who was helping me. With my first pregnancy I backed way off for the last couple of months. With my second, I had a mare who I trusted as entirely as you can trust another being. I knew without a shadow of a doubt that had she stumbled, she would have found a way to catch herself for me. We still did everything (in the arena), including (low) jumping until maybe the last month. But I carried pretty “in” my own body and never felt like my balance was impacted greatly.
What I found made the biggest impact on my riding, was my ability to do it every single day (at least toward the end of the pregnancy). If I took even a single day off, I would have a lot more round ligament pain. With my first pregnancy I was a little more low key about riding and had several periods where I would take 4 or 5 days off, and riding the first day after a break was more difficult. With my second pregnancy I was trying to keep a horse in shape to start showing at a high level right after I had the kid, so I was much more structured and serious about my rides. I felt great as long as I rode every single day. I don’t think I ever took more than a day or two off at a time.
After having gone through both of those, I think I preferred the more low-key-about-riding approach. But with that being said, I recovered super fast from the second pregnancy and have to imagine that staying more flexible and fit because of the riding helped with that. Also, the kid that was in there while I was riding pretty seriously is the one who is a rider through a through. Coincidence? Well, maybe, lol!
Another important piece, though, was my OB/GYN’s willingness to entertain my riding. His daughters were taking riding lessons at the time, so he “got” the riding thing, and didn’t think that I needed to curtail the activity entirely. He was supportive of my riding as long as I paid attention to my own comfort level and backed off appropriately. With that being said, we didn’t entirely agree, and he was not totally thrilled at my activity level in the end. In hindsight, he was right (of course), those extra months of riding were really unnecessary to my horse’s well-being, and while they didn’t cause any problems, it certainly would have been reasonable to take that time off.