Once pregnant, many women tend to eat more and exercise less, or not at all.
However, those with uncomplicated pregnancies should engage in at least 20 to 30 minutes of moderate-intensity physical activity a day, for a minimum of three days a week, but ideally on most days of the week.
This is among the 10 points outlined in Singapore's first set of guidelines on physical activity and exercise for pregnant women that was launched yesterday. It seeks to encourage pregnant women to exercise for better health outcomes for themselves and their children.
Physical activity in uncomplicated pregnancies is not associated with miscarriage, stillbirth, foetal anomalies, preterm birth and neonatal death, and it is safe for pregnant women to exercise into the third trimester.
The guidelines recommend that pregnant women do a variety of aerobic and resistance training activity. Aerobic activity can include brisk walking, swimming, stationary cycling and low-impact aerobics, while resistance training, such as squats and lunges, is appropriate.
Activities to avoid in pregnancy include contact sports, such as basketball or football, scuba diving - due to the risk of decompression disease to the foetus - hot yoga and hot pilates.
Professor Tan Kok Hian, head and senior consultant of the Perinatal Audit and Epidemiology Unit at KK Women's and Children's Hospital, which took the lead in developing the guidelines, said they are meant to not only encourage women to exercise but also to allay the fears that some women have about exercising during pregnancy.
That said, women who were not exercising before their pregnancy should take it easy and discuss it with their doctors.
They can start with simply being more active and gradually increase the time for exercise, said Prof Tan.