In the 1st month of pregnancy, the fetal baby is still very small and the pregnant mother’s uterus is not significantly enlarged, so there will be no significant changes in body shape. If a mother with a second child has an apparently enlarged belly in the first month of pregnancy, there are two main common reasons for this: the first, obesity from premature weight gain during pregnancy. Pregnant mothers with normal pre-pregnancy weight can gain 11.5-16kg throughout pregnancy, and can have no or slight weight gain in the first 3 months of pregnancy. If there is a significant weight gain in early pregnancy and the belly increases, pregnant mothers need to be alert to control the reasonable weight gain during pregnancy to avoid the occurrence of obesity and related metabolic diseases during pregnancy. The 2nd one, large belly due to abdominal relaxation caused by separation of the rectus abdominis muscle. Because the pregnant mother after the first baby, the abdominal muscles are not well repaired about, if allowed to develop, pregnancy is prone to low back pain, labor is also easy to use the force. So you need to do proper sports to enhance the strength of the body’s core muscle groups, but it is best to do so under the guidance of a professional fitness instructor and yoga teacher.