It is best not to drink coffee during menstruation, as it can have an effect on the body. The main reasons are as follows: 1) Drinking coffee during menstruation may cause breast swelling and pain to worsen, and may also stimulate the body, leading to more intense menstrual cramps. 2) Coffee contains caffeine, which stimulates the nerves and cardiovascular system, leading to irregular menstruation, prolonged menstruation, and increased bleeding, etc. 3) Drinking coffee during menstruation may increase the amount of hormones, leading to many gynecological diseases, and may also trigger endometriosis. hormones, leading to the emergence of many gynecological diseases, but also may trigger a variety of diseases such as endometriosis, which will have a direct impact on the body, and at the same time, many women drink coffee after the impact of sleep, often overstimulated, but also may be anxious and irritable, depressed and other problems, aggravating the menstrual response.