Pregnancy 18 weeks stomach slightly smaller, may be malnutrition, is a common situation; if significantly smaller, suggests that there may be abnormal fetal development, is not normal. 1. Slightly smaller: 18 weeks of normal pregnancy, part of the pregnant woman’s stomach will not be obviously pregnant, if the early pregnancy reaction is obvious, the pregnant woman’s nutritional intake is insufficient, which leads to the pregnant woman’s weight growth is not obvious, there may be a slight decrease in the stomach is more common, do not have to worry about it too much, pay attention to nutritional supplementation can be. 2. Obviously smaller: suggests that there may be abnormal fetal development, first of all, check the gestational week, according to early ultrasound, roughly check the gestational week, roughly calculate the size of the fetus, and then determine whether there is fetal growth restriction. Comprehensive judgment is made based on the various indicators of the fetus. Therefore, if the stomach becomes smaller at 18 weeks of pregnancy, the first thing to do is to assess the extent of the reduction. If the reduction is mild, it is usually due to malnutrition, so you can eat more fresh vegetables and fruits and high-protein food to meet the needs of the growth and development of the fetus. If it is obviously smaller, it suggests that there may be growth and development abnormalities, and it is recommended to consult the hospital in time to improve the examination and clarify the intrauterine development of the fetus.