The black line on the belly appears after the fourth month of pregnancy, depending on the individual’s constitution, and some women may not have a black line throughout the pregnancy. The formation of the black line is mainly due to the pigmentation in the woman’s body. After delivery, the black line can be gradually reduced and disappeared by applying appropriate medication or with the extension of time. If you are pregnant for the first time, the stretch marks will appear purplish red, and if you are pregnant for the first time, the color of the stretch marks will be white. You can also tell whether you are pregnant for the first time or for the first time by the change in the color of the stretch marks, and the stretch marks will not disappear easily after delivery.