The preparations for the first three months of a man’s pregnancy include pregnancy-related examinations and improvement of his physical health. 1. Pregnancy related examination: including routine semen examination, checking whether the sperm vigor, quantity and density are normal; checking whether the epididymis and vas deferens have deformity, tuberculosis, obstruction, etc.; checking whether there is any sexual dysfunction, whether there is any abnormality in the development of the penis, etc.. It is also necessary to check whether the adrenal gland, pituitary gland and thyroid gland function are normal and whether they affect the normal growth of sperm; and check whether male sperm immunization is normal. 2. Improve physical health: quit smoking, limit alcohol, and develop a good lifestyle; eat reasonably, exercise properly, and get enough sleep; relax through physical exercise, listen to music, etc., and keep a happy mood. Boys prepare for pregnancy in the first three months to do the preparation there are other, it is recommended to go to a regular hospital by a professional physician for pregnancy method guidance and projected coitus time, to improve the rate of conception, if you are not feeling well, please consult a doctor in a timely manner.