Reddit mentions of Runner's World Guide to Running and Pregnancy: How to Stay Fit, Keep Safe, and Have a Healthy Baby

I ran throughout my pregnancy. Up until 33 weeks when the recovery from the running began to take up my whole day, and I had to choose - do I want to run and spend the rest of the day on the couch or not run and participate in life? It's not that running itself ever got especially hard, it was the recovery that was time consuming. A simple 3 mile run made me feel like I was recovering from a hard and hilly half.

Until then I ran just as I always had, almost daily, but I just tried to keep my heart rate and body temp low. So this meant always running at a conversational pace, not at race pace and often running on a treadmill in front of a fan. Gradually, I had to take walk breaks and not just run the whole time. My easy paces went from 9:00 mile to 12:30 miles and eventually with walking breaks to 15:00 miles. At that point recovery was getting hard too, so I said eff it, and I just walked and used the elliptical up until the due date.

This book was my guide.

Just pay attention to your body. As an experienced runner, you will know when it's time to walk or cut back. The only problem (as an experienced runner) will be your ego/pride keeping you from slowing down. Just remember every mile you cover is a mile further than 99% of the population will go today, and every step is a step toward health and fitness that you won't regret, no matter how slow you go.

Also, drink TONS of water - TONS. It will help prevent Braxton-Hicks contractions.

I really feel like running/being a runner helped me through the athleticism of labor and gave me a speedy physical recovery from delivery.

I've had two kids - check out the book [Runner's World Guide to Running and Pregnancy] (https://www.amazon.com/Runners-World-Guide-Running-Pregnancy/dp/1579547478). I ran throughout my first and some of my second trimesters, but (1) I was usually soooo tired, all I wanted to do was sleep, let alone get out the door and run, and (2) I had placenta previa, especially in my second pregnancy, so I was told not to exercise while that was an issue. In general, though, you can keep running throughout, and I know many women who have run half marathons while pregnant.

Not pregnant, nor have I ever been, but I know there are some books out there about running while pregnant. For example: Runner's World Guide. I'd suggest just doing research and as everyone else has said to listen to your body. I went to spectate my bf's 1st half marathon and remember seeing a woman who was probably 5 months with a shirt that said "You just got passed by a pregnant woman" on the back :)