Exercise during pregnancy: SOGC/ CSEP Position paper
Traditionally, pregnant women have been told to reduce their physical activity levels. These suggestions have been based around fears that raising core temperature during embryogenesis may increase risk of congenital anomalies and shift blood away from the developing child resulting in disturbances in growth. However, are these fears true?
The Society of Obestetricians and Gynaecologists of Canada (SOGC) and the Canadian Society for Exercise Physiology (CSEP) published a position paper addressing basic recommendations for women during and after pregnancy. The summary points are below presented in question-answer format, followed by a link to the full text.
Who should exercise?
"In uncomplicated pregnancies, women with or without a previously sedentary lifestyle should be encouraged to participate in aerobic and strength-conditioning exercises as part of a healthy lifestyle." (p. 334)
What are absolute contraindications to exercise?
The position paper states that pregnant women with the following conditions should not exercise:
- ruptured membranes
- preterm labour
- hypertensive disorders
- incompetent cervix
- growth restricted fetus
- high order multiple gestation (greater than or equal to triplets)
- placenta previa after 28th week
- persistent 2nd or 3rd trimester bleeding
- uncontrolled type 1 diabetes, thyroid disease, or other serious cardiovascular, respiratory, or systemic disorder
Women with the following conditions should move toward adopting exercise with caution. A medical doctor should be consulted:
- previous spontaneous abortion
- previous pre-term birth
- mild/moderate cardiovascular disorder
- mild/moderate respiratory disorder
- anemia (hemoglobin less than 100 g/L)
- malnutrition or eating disorder
- twin pregnancy after 28th week
- other significant medical condition
What screening tool should be used when considering exercise for pregnant women?
"The Physical Activity Readiness Medical Examination for Pregnancy (PARmed-X for Pregnancy) is a tool developed by the Canadian Society for Exercise Physiology and endorsed by the Society of Obstetricians and Gynaecologists of Canada and Health Canada (and available through CSEP's web site ...) for screening women interested in participating in physical activity during pregnancy." (p. 334)
When may be the best time to initiate an exercise program?
Likely second trimester. The first trimester often presents with great nausea, vomiting and profound fatigue. (p. 335)
How should a pregnant woman initiate cardio into an exercise program?
Previously sedentary women should start with 15 minutes of continuous exercise three times a week and then increase to 30 minute sessions four times a week.
"Episodic maximal exercise by pregnant women in a research setting appears to be safe for mother and fetus" (p. 335)
What cardio activities would be recommended?
"Brisk walking, stationary cycling, cross-country skiing, swimming, or aquafit are aerobic exercise that cause less trauma to the joints and ligaments and less bouncing up and down of the centre of gravity than running or jogging." (p. 335)
How intense should exercise be?
Generally, she should be able to maintain a conversation during the exercise. If she cannot, then exercise less intensely.
Target heart rate zones for aerobic exercise in pregnancy
- Less than 20 yrs old: 140 - 155 beats/min
- 20 - 29 yrs old: 135 - 150 beats/min
- 30 - 39 yrs old: 130 - 145 beats/min
- 40 yrs or older: 125 - 140 beats/min
Guideline for elite athletes who are pregnant
Have obstetric care provider supervise your status.
When should I stop exercising?
Seek medical help if experiencing the following:
- excessive shortness of breath
- chest pain
- painful uterine contractions
- leakage of amniotic fluid
- vaginal bleeding
What are considerations for exercise postpartum?
- may need to reduce intensity
- slowly increase training for women who have had caesarian delivery
- initiation of pelvic floor exercise in the immediate postpartum period may reduce the risk of future urinary incontinence
What are considerations for breastfeeding women?
Although exercise does not negatively affect milk production or composition, lactic acid has been shown to be increased in the breast milk of women exercising at maximal intensity, but not in those exercising at moderate level. There is controversy as to whether this short-term increase in lactic acid makes the breast milk less palatable to the nursing infant. Mothers who find that their baby does not feed as well right after exercising may consider feeding the baby right before exercising (which may also make the breasts more comfortable during exercise), postponing feeding until 1 hour after exercising, or expressing milk prior to exercising to be used after exercising. The growth of breastfeeding babies of exercising women is normal, even for infants whose mothers are losing weight as part of their exercise regimen." (p. 338)
Speak with your medical doctor before initiating exercise programs.
Davies, GA.L.; Wolfe, L.A; Mottola, M.F.; and MacKinnon, C. (2003). Joint SOGC/CSEP Clinical Practice Guideline: Exercise in Pregnancy and the Postpartum Period. Can. J. Appl. Physiol. 28(3): 329-341
Full text of position paper click here