|Image from World Obesity Federation Image Bank*|
However, keep in mind that there are plenty of women who don't do these things and still have a vaginal birth. And there are plenty of women who do everything "right" and still end up with a cesarean. There's certainly not a one-to-one relationship between exercise and cesareans. But being as proactive as possible in your health habits during pregnancy may lessen the risk for complications or for an unplanned cesarean.
Personally, in my first pregnancy I didn't exercise that much. I had quite a bit of bleeding and spotting at first and was told not to do much, plus we had a major move in the middle of it all which meant that most of my non-work time was spent on packing and unpacking from the move. I felt pretty out of shape by the end of pregnancy.
In my second and third pregnancies, I exercised quite a bit. I wasn't running marathons or anything, but I did walk regularly, and added in swimming, water aerobics, and prenatal yoga as my schedule allowed. If all else failed, I ran the stairs in my house. I felt SO much better and had way more stamina.
In my fourth pregnancy, I was taking care of my seriously ill mother as well as my three young children. It was hard to find time to sleep, let alone exercise, but I did still manage to walk some. I fit in swimming or stairs where I could but I didn't get nearly as much exercise as the second and third pregnancies. By the end, I felt the difference.
Here is the abstract for a recent study that supports the idea that regular exercise in pregnancy might cut the risk for cesarean.
For me, exercise didn't make much difference in which pregnancies ended in cesarean, but it sure did make a difference in how I felt by the end of pregnancy! And I think it helped me lower my risk for complications like blood pressure issues etc., which I never got despite being "morbidly obese" and a much older mom.
So I'm a major fan of getting regular exercise in pregnancy. It doesn't have to mean running a marathon, but simply doing regular movement of some sort seems to be a common-sense thing to do. And if it lowers your risk for cesarean somewhat, all the better.
However, exercise programs are often pushed mainly for "obese" women. Frankly, ALL pregnant women should be encouraged to get more exercise, not just women of size. High-BMI women may benefit the most from it, but women of all sizes benefit from regular exercise.
As long as you don't have any medical contraindications, exercise is just a common-sense thing to do in pregnancy.
*Isn't it telling that I couldn't find a good positive picture of a pregnant woman of size exercising? Many of us do it, so why aren't there many good pictures of that? The very few pictures I did find were problematic for various reasons. Most images in articles about exercise for heavier pregnant women actually showed pregnant women of average size, or the images were patronizing and stigmatizing. Please, if you have a good picture of yourself pregnant and exercising, I'd appreciate it if you shared it with me for use in the future.
Am J Obstet Gynecol. 2016 Aug 23. pii: S0002-9378(16)30579-8. doi: 10.1016/j.ajog.2016.08.014. [Epub ahead of print] Exercise during pregnancy and risk of cesarean delivery in nulliparous women: a large population-based cohort study. Owe KM1, Nystad W2, Stigum H2, Vangen S3, Bø K4. PMID: 27555317
...OBJECTIVE: The purpose of this study was to investigate the association between exercise during pregnancy and cesarean delivery, both acute and elective, in nulliparous women. STUDY DESIGN: We conducted a population-based cohort study that involved 39,187 nulliparous women with a singleton pregnancy who were enrolled in the Norwegian Mother and Child Cohort Study between 2000 and 2009. All women answered 2 questionnaires in pregnancy weeks 17 and 30. Acute and elective cesarean delivery data were obtained from the Medical Birth Registry of Norway. Information on exercise frequency and type was assessed prospectively by questionnaires in pregnancy weeks 17 and 30...RESULTS: The total cesarean delivery rate was 15.4% (n=6030), of which 77.8% (n=4689) was acute cesarean delivery. Exercise during pregnancy was associated with a reduced risk of cesarean delivery, particularly for acute cesarean delivery...The largest risk reduction was observed for acute cesarean delivery among women who exercised >5 times weekly during weeks 17 (-2.2%) and 30 (-3.6%) compared with nonexercisers (test for trend, P<.001). Reporting high impact exercises in weeks 17 and 30 was associated with the greatest reduction in risk of acute cesarean delivery (-3.0% and -3.4%, respectively). CONCLUSION: Compared with nonexercisers, regular exercise and high-impact exercises during pregnancy are associated with reduced risk of having an acute cesarean delivery in first-time mothers.