The following tests are required during the preparation for second pregnancy: i. Routine examination of the reproductive system. Women who are preparing for second pregnancy should routinely undergo ultrasound examination of the reproductive system, routine examination of vaginal secretions, six hormone tests and examination of some pathogens of sexually transmitted diseases. Routine laboratory tests. Such as blood sugar, liver function, hepatitis B three systems, urine routine, thyroid function, etc. Third, cardiac examination. Routinely do electrocardiogram examination, and if necessary, do cardiac ultrasound examination. Chest X-ray examination. V. Male examination. When preparing for second pregnancy, not only women need to be examined, but also men need to undergo routine examinations, such as routine semen chemistry, chromosomal examination and examination of pathogens of sexually transmitted diseases. If a pregnant woman has a history of abnormal pregnancy or childbirth, she needs to undergo a targeted systematic and comprehensive examination.