The fact that being too thin may affect the birth of a child is subject to individual differences. For some women, if there is still unsatisfactory weight gain during pregnancy, it is considered to be related to insufficient nutritional intake, which may result in delayed intrauterine development of the fetus, thus increasing the chance of miscarriage and preterm delivery. In addition, pregnant women who are too thin may also have pelvic stenosis, which may make it impossible for the fetus to be delivered vaginally during vaginal delivery and may require a cesarean section. Of course, if the pregnant woman is only thin, and does not have any other physical diseases, and all organs are relatively healthy, it will not affect the birth of a child. Pregnant women are advised to have good living and eating habits, eat more protein and vitamin-rich foods, and undergo regular checkups.