Recommendations for various sports & exercise during pregnancy:
Walking: Generally recommended before, during and after pregnancy. To start with, go for a 16 or 17 minutes mile then adjust the speed according to comfort levels.
Jogging: If already a regular jogger, then this can normally be continued for a while so long as it remains comfortable. Take on plenty of water and do not overheat. Concentrate on not falling over.
Golf: Normally no problems to continue, however, balance can become a problem later in the pregnancy.
Horseback riding: The risk of falling and too much jolting of the abdomen puts this into the unsafe category.
Climbing/Hiking: Generally OK, but not at elevated heights of over 3000 Metres due to the reduced oxygen available.
Swimming: Generally recommended. Good exercise for the large and small muscle groups. Good for heart conditioning. Gentle on joints and ligaments. Driving should be avoided.
Tennis: If one already practices tennis, then a reduced paced game should be alright to continue. Beware of change in balance. Do not stretch the extra for that match-winning ball.
Skiing, Snowboarding, etc.: Not advised. High risk of falling makes these activities dangerous.
Aerobics: Generally recommended if the low-impact version is followed. Water aerobics is a very good conditioning method to use during pregnancy.
Badminton: Generally OK during the early stages of pregnancy.
Boxing, Taekwondo, Karate, Judo, etc.: No
Football, Soccer, Basketball, Hockey, Rugby, etc.: No
Sex: Refer to this article
Yoga: Gentle regimes are very good at toning strengthening the body.
Gymnastics, Trampolining, etc.: Generally not recommended during pregnancy, especially not competitively. High risk of falling.
Scuba diving: No. Very dangerous for the baby.
Fishing: Fine to continue fishing, but this is not going to improve conditioning very much (unless there is a good long walk to get there). Take plenty of water and food along if sitting on the river bank for hours on end.
Cycling: Generally OK to continue when pregnant. Check with your doctor if you have any pelvic problems.
Dancing: Generally good exercise. Take care not to fall or participate in too energetic/jerky a dance style.