Guys preparing for pregnancy need to stop smoking and drinking for more than three months. The process of sperm development to maturity takes about 90 days, so it is better for a cycle of sperm not to be disturbed by external factors before maturity. For guys who are preparing for pregnancy, they need to quit smoking and drinking for more than three months so that the sperm in this cycle can mature before having sex, which can improve the quality of the sperm. In addition to quitting smoking and drinking, boys should also strengthen exercise in daily life to prevent and control chronic diseases. Avoid prolonged exposure to high temperatures, toxic and radioactive environments, and avoid a physically damaging lifestyle such as staying up late and being sedentary, as well as paying attention to diet and nutrition. The process of preparing for pregnancy can consult the advice of professional doctors.