Background: Exercise during pregnancy is associated with numerous health benefits, including the prevention and control of gestational diabetes, control of excessive weight gain, reduction of lower back pain complaints, and positive effects on maternal health and quality of life.

Objectives: To assess the knowledge and practice of pregnant towards physical activity during their pregnancies in the eastern province in Saudi Arabia.

Methodology: A sample of 388 female conducted in the antenatal care clinic at primary health care centers ( khobar, Dammam, Qatif ) including the low risk pregnancies. All participants were assessed using self–administered questionnaire that was consisted of 3 sections: a) sociodemographic questions, b) Knowledge, c) Practice. Data was analyzed by SPSS. Consent was obtained.

Main results: The mean knowledge score of participants was 13.7±3.6 (69.5%), and it was strongly associated with education, p=0.009.prevalence of physical activity in our sample was (42.5%). Occupation and education were significantly associated with practice, p= 0.001, p= 0.000 respectively. The association between knowledge score and practice was also significant, p=0.000.

Conclusion: Although knowledge of participants was above the expected, more efforts are needed to assess the barriers of physical activity during pregnancy and develop individualized programs for pregnant attendees in PHC centers.