Physical activity during pregnancy is generally considered safe and beneficial for both the pregnant woman and her fetus. The overall aim was to investigate pregnant women's pre-pregnancy and early pregnancy physical activity and its associations with maternal characteristics and pregnancy outcomes.This cross-sectional study combined data from the Maternal Health Care Register in Västerbotten (MHCR-VB) and the Salut Programme Register (Salut-R). Data were collected from 3,868 pregnant women living in northern Sweden between 2011 and 2012.Almost half of the participants (47.1%) achieved the recommended level of physical activity. Compared to the women who did not achieve the recommended level of exercise, these women had lower BMI, very good or good self-rated health, and a higher educational level. No significant associations could be established between physical activity levels and GDM, birth weight, or mode of delivery.Positively, a considerably high proportion of Swedish pregnant women achieved the recommended level of physical activity. Factors associated with recommended physical activity level were BMI ≤30 kg/m(2), very good or good self-rated health, and higher educational level. Our findings emphasize the need for health care professionals to early detect and promote fertile and pregnant women towards health-enhancing physical activity, especially those with low levels of physical activity and overweight/obesity, to improve overall health in this population.