Once in a while a bad mood will not have much effect on the quality of sperm, if the long-term bad mood will affect the quality of sperm. 1. No effect: if only once in a while a bad mood, the impact on the body’s endocrine is not particularly large, the impact on the quality of sperm is also not large, generally do not need to worry too much. 2. Impact: If a long time of bad mood, or too much mental stress, etc., will have an impact on the male body’s endocrine system, the body’s hormone levels will be disturbed, will affect the quantity and quality of the sperm, so in the preparatory period of men should pay attention to regulating the mood, to avoid too much mental stress. For men who are preparing for pregnancy, if they are worried about poor sperm quality, it is recommended that they undergo a sperm quality test before pregnancy, and it is best to get pregnant in a state of good sperm quality.