Pregnancy is an important stage in a woman’s life, and an important period for maintaining oral health. During pregnancy, women’s life patterns change, the number of meals increases, they love snacks and sweet and sour foods and often neglect oral hygiene care. In addition, pregnant women are prone to gingivitis during pregnancy if they do not pay attention to oral hygiene due to endocrine changes. Research shows that the oral health of pregnant women directly affects the oral health of infants and children, so the oral health care of pregnant women is particularly important. Pregnant women’s oral health care is mainly divided into two periods: pre-pregnancy and pregnancy. 1, pre-pregnancy oral examination, eliminate the hidden dangers of the oral cavity during pregnancy. Various latent oral diseases are prone to occur during pregnancy. Therefore, a comprehensive oral examination should be conducted before pregnancy to deal with oral problems in time and eliminate all oral hidden dangers. (1) Filling of dental caries (filling): Early treatment of dental caries to avoid deepening of caries in the course of pregnancy. For teeth already suffering from pulpal and periapical inflammation immediately do perfect pulpal and root canal treatment to avoid attack during pregnancy. (2) Prevention of gingivitis and periodontal disease during pregnancy: Ultrasonic scaling (commonly known as scaling) for existing gingivitis and systematic periodontal treatment for existing periodontitis. Also pay attention to mastering mechanical plaque control methods such as brushing. (3) Extraction of residual roots, crowns and wisdom teeth that cannot be treated by filling in the oral cavity, and elimination of possible inflammatory lesions. (4) If there are missing teeth, they should be restored in time so as to restore the chewing function, which will help digestion of food and nutrient absorption, and will be beneficial to the health of pregnant women and the growth and development of the fetus. 2, pay attention to oral hygiene during pregnancy, master the correct method of oral cleaning (1) adhere to the effective brushing twice a day, and advocate the use of mouthwash. This is extremely effective to prevent and control gingivitis during pregnancy. For pregnant women who are prone to dental caries (commonly known as tooth decay), fluoride can be used appropriately and locally, such as fluoride coating, etc. (2) Appropriate use of dental floss to remove plaque and soft scale from adjacent surfaces of teeth. (3) Use sucrose-free chewing gum to clean teeth, such as xylitol chewing gum, which can promote saliva secretion, reduce oral acidification, inhibit bacteria and clean teeth, and help reduce the incidence of tooth decay. 3, regular oral health examination, oral treatment at the right time Oral diseases will develop faster during pregnancy, regular examination can ensure early detection, early treatment, so that the lesions are limited to a small area. For more serious oral diseases, should choose the right time for treatment. Pre-pregnancy (first 3 months): a critical period of embryonic development, prone to miscarriage. Oral treatment is not recommended at this stage, and only simple treatment is given to relieve symptoms in case of oral emergencies. Pay attention to avoid X-ray exposure. Mid-pregnancy (April-June): the appropriate period for treatment of oral diseases. Dental extractions are generally not recommended during pregnancy, but in case of severe acute inflammation or urgent need to remove wisdom teeth, local anesthesia can be performed during this period after weighing the pros and cons. Late pregnancy (July-September): At this stage, the uterus is more sensitive, and external stimulation can easily cause uterine contraction, and the lying position during treatment can easily cause lying hypotension in pregnant women, so oral treatment should be avoided as much as possible. If it cannot be avoided, it is recommended to lie down towards the left side or change position occasionally during treatment, and treatment should be simple. 4. Establish good habits 1) Use drugs carefully: many drugs are harmful to the development of fetal jaws and teeth, such as tetracycline which will discolor the baby’s teeth and metronidazole (methotrexate), a common oral drug, which may cause malformation, so drugs should be used under the guidance of doctors during pregnancy. (2) Do not smoke and drink alcohol, and avoid passive smoking: Pregnant women smoking, drinking alcohol and passive smoking can easily lead to malformations in fetal development, such as cleft lip and palate. Therefore, in addition to not smoking and drinking themselves, pregnant women should also avoid passive smoking. 5. Develop good dietary habits and reasonable dietary nutrition (1) Women during pregnancy should take sufficient nutrition, including protein, various vitamins (especially vitamin A and D) and necessary trace elements to facilitate fetal development, bone and tooth formation and calcification. (2) Avoid excessive intake of acidic foods that may cause dentin sensitivity. (3) Balance the dietary structure, choose foods that are good for health and non-cariogenic, eat less sweets and reduce snacks.