Pre-operative preparation: First of all, three certificates qualified to submit to the department acceptance of both sides of the ID card, both sides of the marriage certificate, the birth of a child to hand over the family planning information form, the second child needs to be born; check the three certificates need to be carried by both spouses of the original on-site audit, retain copies. (Copy format for A4 printing paper, both sides of the ID card anyway, both sides of the copy on a piece of paper; will both sides of the marriage certificate with a photo side of the copy on a piece of paper; the rest is not to be repeated.) Female: 1, 2-3 days after menstruation (bleeding) fasting check endocrine and thyroid function. 2, 3-7 days after menstruation without intercourse for tubalography. 3, fasting check blood routine, urine routine, coagulation series, liver and kidney function, virus screening, blood type (not limited by the menstrual cycle), 3-7 days after menstruation clean check cervical cytology, leukorrhea routine, gonococcus and chlamydia. Male: 1. Three copies of semen routine report within one year (at least 7 days between two copies); two copies are needed for normal people. 2. Virus screening, blood routine, urine routine, blood type, gonococcus and chlamydia test, etc.