In the fast third trimester, low food intake and weight loss can lead to fetal growth restriction and should be treated with vigilance. Fetal growth restriction is defined as an impairment of fetal growth potential with an estimated fetal weight below the 10th percentile for the same gestational age, which increases the risk of adverse pregnancy outcomes. Low food intake and weight loss of the pregnant woman will affect the mother’s nutritional supply to the fetus, which will affect the growth and development of the fetus, resulting in fetal growth restriction. In this case, they should go to the hospital for timely consultation and treatment under the guidance of the doctor. Improve the nervous state of mind of the pregnant woman, increase her energy intake and rationalize her diet. If there is still no significant change in the weight of the pregnant woman after treatment, the pregnancy can be terminated if necessary.