Anyone who is pregnant and wants to work out (or keep working out) should check with their doctor and get the all clear before proceeding.
But to get some general guidelines on what kind of exercise people can safely do during pregnancy, BuzzFeed Life talked to Dr. Daniel Roshan, assistant professor in the division of maternal-fetal medicine at NYU School of Medicine and (via email) to Mary Jane Minkin, clinical professor of obstetrics and gynecology at Yale University School of Medicine. Both Roshan and Minkin recommend exercising during pregnancy for fewer complications during labor and delivery. Roshan says that it's fine to exercise throughout pregnancy as long as it feels OK to do so and you've cleared it with your own doctor based on your unique pregnancy and health concerns. The general limiting factor, he says, will be that the further along you are, the harder it becomes to move around.
Minkin says that walking, running, swimming — whatever movement you love — should be fine as long as it doesn't raise your core temperature too much, because that's not good for the baby. Roshan says that the core temperature should not go above 100ºF.
There are some exceptions, though. Roshan explained that anyone who has high blood pressure, heart disease, or a short cervix should not exercise during pregnancy. If the baby is atypically small or showing other problems with growth, the mother should not exercise. Minkin said that anyone with a history of preterm labor should not exercise while pregnant. Otherwise, it's game on — with a few more important guidelines...