When you are pregnant, you usually need to provide your ID card, medical card, marriage certificate, family register, medical insurance card for those who are enrolled in medical insurance, and other documents, as well as laboratory and ultrasound sheets. Some hospitals require some medical checkups in the community and a mother and child health handbook before you can go to the hospital to build a file. As the required documents vary from hospital to hospital, it is recommended that pregnant women consult the hospital where they want to have a file opened in advance to avoid inadequate preparation that may affect the smooth opening of the file. Pregnancy documentation is usually done in the third month of pregnancy because the fetus is unstable and prone to miscarriage when the pregnancy is early. When the placenta is formed in the third month or so, the pregnancy is relatively stable, and at that time you can start to build a pregnancy file. Generally speaking, the file-building booklet will contain many notes and fixed examination times to prepare for the future delivery. The purpose of the pregnancy file is to provide better management of the pregnancy, to follow up on high-risk pregnancies, and to ensure the safety of the pregnant woman and the fetus during the pregnancy. It is better to have the file opened in the hospital where you are going to give birth, so that the doctor can have a comprehensive information about the pregnant woman and her maternity checkups and ensure the continuity and completeness of the information. In addition, it is important to fill in the correct personal information when opening the file and to visit the hospital in your real name.