Exercise During Pregnancy- Making The Case

The body of evidence supporting exercise during the pregnancy and the post-partum period is mounting. In the last twenty years more and more research has been conducted in this area, and I'm certain it is just the beginning of what we will eventually learn. I promised an installment discussing the benefits of exercise and how to fit it into our days, but then this long blog post would be even longer! Instead I"ll break this down into three blog posts, and today we will make the case for pre-natal exercise. 

So, the bun is in the oven! Why should you be motivated to exercise when you perhaps feel nauseated, exhausted, swollen, "fat," etc? It seems odd, but these are the reasons you should exercise. Studies have shown women who exercise regularly during pregnancy suffer less from common pregnancy discomforts, and minimize unnecessary weight gain.

Women who are underweight beginning a pregnancy are urged to gain more weight in order to increase maternal fat stores to help support the pregnancy. Women who are already in possession of adequate, or even more than adequate fat stores are recommended to gain less. The weight of the baby, placenta, enlarging uterus, and expanded blood and fluid volumes comprise the portions of pregnancy weight gain that go away fairly quickly after the arrival of your baby. Any maternal fat stores remaining are what you need to worry about losing in the months following birth. Women who exercise in pregnancy are better set up to get back in shape quicker post-birth, having lessened the amount of weight they would have gained had they remained sedentary; requiring less to lose. I know this speaks to our vanity, but gaining within recommended ranges also has wonderful benefits besides looking better. Let's examine these.

Pregnancy complication rates are lower for pregnant mamas who exercise, eat with good nutrition in mind, and have a healthier weight gain as a result. Gestational diabetes rates are lower in women who exercise before and during pregnancy. This is a health complication not only affecting you and your future health, but your growing baby as well. Not every woman can avoid this complication, but studies have shown us many can through adoptions of healthy lifestyle practices in the child-bearing years. For those that develop gestational diabetes, exercise is an important part of treatment to keep blood sugar in good control, minimizing associated problems.

Downton Abbey fans, will remember Lady Sybil suffered from pre-eclampia, (also known as toxemia), that lead to eclampsia (seizures) resulting in her death. While we are now able to better identify and manage pre-eclampsia; it is still a major pregnancy complication that is not resolved until days to weeks after the baby is born. This complication can lead to an early birth, and resulting problems that often follow. We don't fully understand why pre-eclampsia occurs, or how to completely prevent it. Research to discover the effects of exercise in pregnancy has uncovered some exciting results in regards to pre-eclampsia. One study showed exercising mamas lowered their risk of developing pre-eclampsia by about 30% compared to sedentary mamas. The data suggest exercise during pregnancy is the single most impactful thing you can do to reduce your risk.

What about other risks? Does exercise pose a danger, or a preventive effect? Exercise in mamas identified as low risk and healthy do not stand a higher rate of miscarriage, stillbirth, or pre-term labor/birth than that of sedentary mamas. So, for women who have been medically cleared for exercise, the benefits exercise provides tremendously outweigh any risk it could possibly present.

Let's now consider how exercise impacts labor and birth. In a ground breaking study published back in 1990, exercising mamas had a cesarean section rate of 6% vs. 30% in the group that stopped exercising after becoming pregnant. How awesome! The biggest factor reducing the rate of  cesarean section in these women is a dramatically lower incidence of fetal distress, meaning their babies are better able to tolerate the rigors of labor than their sedentary counterparts. This is exciting because of the benefits fewer cesarean sections would mean for women and babies individually, and within our healthcare system collectively. 

Your little one greatly benefits from your exercise, and the number of these identified benefits are growing and becoming increasingly understood through recent research. Benefit number one: a stronger heart. When your heart rate increases during exercise, so does your baby's. At first this worried doctors who thought this faster heart rate was potentially harmful. What we now understand is your baby is getting a passive aerobic workout in the womb when you exercise. This explains the decreased distress in labor, and a healthy lower heart rate that has been documented for up to a month after birth. Because their heart rate is lower, we know they have a stronger heart muscle that can pump more blood with each beat, which means they can pump blood around their little bodies more efficiently than babies of sedentary mamas. This is a very good thing!

Benefit number two: exercising mamas grow a baby that is leaner than a baby of a sedentary mama. Why do we care, and why would this be desirable? Chubby babies are adorable, right? Research is beginning to show the long-term implications of being born with less fat, rather than more. Studies show leaner babies have a better chance of avoiding childhood obesity, at least through the age of 5, but it stands to reason  this benefit could extend further into childhood and adolescence.  Some experts believe more sedentary mamas having babies with increased fat stores partially explains why our childhood obesity rates have jumped so quickly in the last few decades, and may be key in reducing it in the future.

While I could talk more about study after study, I know it is tedious and perhaps more than you'd care to know. In short, most women are lucky enough to be eligible to receive all these benefits, (and more that we have yet to uncover), because they are identified as low risk and healthy during pregnancy. It is my hope that these benefits will soon become mainstream knowledge for your average woman, and if she chooses not to exercise in pregnancy, at least she will know and understand what she is passing up. Educating mamas is where it all begins!