The idea of pregnant women enjoying regular exercise can cause controversy — just ask tennis superstar Serena Williams. Back in 2017, the insanely fit winner of 23 tennis grand slams made judgement-heavy headlines worldwide simply for declaring her plans: “to keep exercising for as long as possible while pregnant”.
The same year, the authors of Exercise During the Childbearing Year, published in the Journal of Perinatal Education wrote that for generations “pregnant women were treated as if they had an illness and were subjected to a state of confinement. They were advised to relax, avoid strenuous exertion, and minimise stretching and bending for fear of strangling or squashing the baby”.
Expectant mothers will be familiar with being warned off lying on their back, swimming anywhere but a pool, lifting anything heavier than a duster, and putting any sort of pressure on their joints.
But a new understanding of the female body during this precious time is showing that there is little to fear from physical activity. In fact, the real health issue is more likely to come from gaining excess weight — aka ‘eating for two’ — and being sedentary for nine months.
According to a report two years ago in the Journal of the American Medical Association (JAMA), “these misguided recommendations” have “evolved into a major contributor to the worldwide obesity epidemic”.
Fifty years ago, gynaecological medicine emphasised the need for women to gain enough weight to provide for healthy foetal growth. Now the coin has been flipped.
In the JAMA report, about 45 per cent of mothers-to-be began their pregnancy in an overweight or obese state, versus 24 per cent in 1983. In addition, nearly half of pregnant women gained more weight in nine months than the amounts recommended by the Institute of Medicine.
The report looked at four key aspects of exercise during pregnancy: safety, benefits, the when and how, and precautions. A meta-analysis of studies with more than 2,500 pregnant women found no risk of preterm birth or low birth weight children among normal weight women who exercised.
Moderate exercise is now recommended even for women who did not exercise before becoming pregnant, with pregnancy considered an excellent time to introduce healthy lifestyle habits because the mother is highly motivated.
The list of benefits is lengthy and includes: less macrosomia (birth of children weighing more than 8 pounds, 13 ounces), less gestational diabetes, less preeclampsia, fewer Caesarean-section deliveries, less low-back pain, less pelvic girdle pain, and lower frequency of urinary incontinence.
There is another benefit too: stress relief. Almost every report on exercise during pregnancy has shown a positive impact on mental well-being, notably birth anxiety.
Some exercises should be avoided though for safety, notably long-distance running, which could raise body temperature and cause dehydration. Also exercising at greater than 90 percent of maximum heart rate, lifting heavy weights (or performing isometrics), or getting in a supine position during the last two trimesters.
“Pregnancy is no longer considered a state of confinement,” commented the report’s exercise and health experts. “An active lifestyle during pregnancy is safe and beneficial.”
The British Journal of Sports Medicine, stated that as long as a regimen feels good and doesn’t pose a major risk of falling or being hit in the belly, in general women can continue any exercise they were doing before pregnancy — in fact, it’s recommended.
Current guidelines say that healthy pregnant women with no pre-existing conditions should aim for around 150 minutes of moderate activity per week, incorporating a mix of aerobic activity and resistance training.
“The key is hydration,” explained Jennifer Aquino, MD, an ob-gyn at New York academic medical centre NYU Langone Health.
“Water helps form the placenta and amniotic sac, and it helps to keep you cool during exercise. Since overheating is one of the biggest concerns of exercising while pregnant, you want to hydrate well, wear breathable clothes, and avoid any hot yoga. It’s also a good idea to have a snack after working out to make sure your blood sugar doesn’t get too low.”
An interesting twist on this topic, is that for women trying to get pregnant but struggling, exercise could also be the magic key.
A study in the American Journal of Epidemiology of 50,678 women found that moderate levels of exercise have positive effects on fertility. Medics advise that women trying to conceive should exercise for thirty minutes a day, three times a week, with two, 30-minute strength training sessions.
Some days could include non-hot yoga for an hour. It uses a specific series of stretches that have a positive effect on reproductive health, and women worldwide are reporting great results. Time for a pregnancy paradigm shift.