Only certain women should be discouraged from exercising vigorously during pregnancy: those who have suffered more than one miscarriage, those who had any bleeding or cramping in early pregnancy, and those who have been recommended to take bed rest.

Exercise, other than moderate walking and daily activities, like light running for the bus, should then be avoided. If your doctor has recommended bed rest, avoid any unnecessary exercise. Whatever weight you gain in pregnancy will just have to be worked off vigorously once you have had your baby. You may be able to resume exercising later, once your doctor has advised more activities. Exercise and sporting activities, in themselves, will not cause a miscarriage. Aerobics, twisting exercises, jogging, bicycling, and certainly swimming are all safe in normal pregnancies.

Swimming. Long known to be one of safest forms of exercise, comes in for a lot of suspicion during pregnancy. Many women have heard stories that the water might enter the vagina and so adversely affect the fetus. There is no danger of water getting into the vagina, and by implication the uterus, neither will it affect your bloodstream. So, unless you have been warned against it, and if you enjoy swimming, it is an excellent form of exercise fro the pregnant woman.

Competitive sports such as squash and raquetball should be avoided—unless you play them regularly—as sudden burst of excess energy could cause a physical injury. A prolonged risk in body temperature can have a harmful effect on the developing fetus. So avoid more than thirty minutes of intense exercise, as this may raise the core temperature of your body. Similarly, prolonged exposure to heat, such as that from a sauna or whirlpool bath, should be avoided or kept to just a few minutes. Jogging is fine but not at marathon levels.

Needless to say, certain sports that carry a risk of physical danger should be avoided: horseback riding and mountaineering could lead to falls, skiing has its known dangers, and hang gliding is definitely out.

Burn injuries

The trauma from something as frightening as receiving severe burns will not necessarily lead to miscarriage, unless the damage to your body was extensive and life threatening, causing major damage. Minor burns do not cause miscarriages and are not dangerous in pregnancy.